Having received several requests I scanned the pages of the land before time illustrated story book which contain an illustration (running over both sides which are too large to be scanned as one though) refering to the Oasis scene:


The full text of the Oasis scene (brought up earlier in this thread, but I'm posting it again to spare you the browsing;)) reads:
(...) A long time passed and the brave little
group (Littlefoot, Cera, Ducky, Spike and Petrie) was getting more
tired and hungry with each plodding step. At least
they left the mountains behind. Now they were in a
hot, sandy desert. "I tired," moaned Petrie. "Way
to Great Valley too great way." "We're almost
there," cried Littlefoot. "Don't give up
now." Suddenly Spike became alert and sniffed the air. "He
must smell food," said Ducky. "It's the only thing
that would wake him up." Spike snorted and galloped
over a small hill. The others followed, staring in
wonder at what they saw. There was a small spring of water
surrounded by a group of thin gray-noses (Another word
for Ducky's sort). Near the spring but standing apart
was a cluster of trees full of delicious-looking
green-food, surrounded by a group of fat
crown-heads. Littlefoot and the others raced down the hill, yelling and
cheering. But they got closer, they saw the hard looks
on everybody's face, and the cheers died in their
throats. A stern-looking gray-nose came up to them and said,
"What do you want, little ones?" "Food!", Littlefoot
cried. "And water, yep, yep," Ducky added. A fat
crown-head waddled up and said, "No food!" "You may
drink," said the grey-nose to Ducky. "You are a big-mouth
like us. But," he continued pointing at the rest of
the group, "no water for them." "But they need
drinks, too!" Ducky protested. They're my
friends." "These are your friends?" said the fat crown-head.
"A threehorn? A longneck, a spike-tail and" - he
pointed to Petrie - "and whatever that is." "Yes, run
away quickly," said the grey-nose to Ducky, "before
spikes and horns grow on you." Cera couldn't believe
what she was hearing. She had never realized before
how foolish it was to dislike someone just because
he looked different. All she knew now was that they
all needed food and water. She reared up her head
and said firmly, "We're hungry! All of us!" The
thin grey-nose stared at her. "And so are we," he
finally said. "Then why don't you share the water with
the crown-heads?" said Littlefoot. "And hey could
share the food with you. Then you wouldn't be hungry
and they wouldn't be thirsty." "No, no, no," said
the crown-head and the grey-nose at the same
time. "Well, if you don't change your minds, all of you will
die," said Cera. "Why don't you like each other
anyway?" Ducky asked. "The crown-heads are from the
other side of the swamp," said the gray-nose. "I
don't see anything wrong with that," said
Littlefoot. "This is silly. I'm hungry," cried Cera. "Let's go
somewhere else to look for food together." And with that
the small group marched away. The grey-nose shook his
head. "I'll never understand that young ones," he said. The
crown-head nodded and went back to guard the
food. (...)
The land before time Illustrated Story Book is however the only source we got about the scene. It is possible that the authors of the book were given planning sketches for the movie while it was still in production and wrote the book without having ever seen the movie. It is however down to speculation. There is no shred of evidence that the oasis scene has ever actually been produced. I don't think Don Bluth ever refered to it when talking about outcut scenes. Mr. Bluth mostly refered to the Sharptooth scenes that were cut for being deemed too scary by Steven Spielberg and George Lucas. Lack of mention by Don Bluth is not a certain sign that the oasis scene was never produced; after all Don Bluth never referred to the scene in which after his birth Spike was lured with berries to follow the group.
Now with that berrie scene the situation is quite the opposite of the oasis scene in terms of source material. We know for a fact that the scene was produced since screenshots of it made it into cinema showcases as well as into the book "Friends in Need":

However, while we got the image of the scene we don't have any references to any dialogue or other content of that scene. There just isn't any written reference to it at all. This is all you will find in "Friends in Need" about the meeting with Spike:
The next day, among some tall dry weeds, Ducky stumbled upon a nest with a lone egg. The egg was snoring!
Ducky tapped the shell and called, "Hello in there. You should come out now, you should." The egg cracked open, and a sleepy-eyed baby spike-tail gazed at her dreamily.
Ducky said to the others, "Can he come with us? I have named him Spike, and he is all alone, too. Yes, he is."
Spike joined the group, and they continued their journey across the lonely land. Everyone except Cera seemed happy to have some company.
The book "The Search for the Great Valley" is even more curt when it comes to Spike's joining the group. This is all it says:
Soon a little spike-tail, whom Ducky named Spike, joined the weary group.
Finally the Illustrated story book is a little more detailed about Cera's reservations against Spike, but it doesn't make any reference to the berries either:
The next morning the four of them trudged on across the barren land. When the bright circle was high in the sky, Ducky came upon a nest with one unhatched egg lying among broken shells. Strange sounds were coming from the egg - snorring, then yawning. Ducky gave a cry of delight and tapped the egg. It started to crack open. A sleepy head appeared. Ducky quickly peeled away the rest of the sell, and there stood a sleepy-eyed spike-tail.
"You are a spike-tail, so I will call you Spike," Ducky said.
The rest of the group came running up. "This is my new friend, Spike," said Ducky. "Can we take him with us? Huh? Huh?"
"He'll slow us down," Cera said. "All spike-tails can do is eat and burp. Sharptooth will catch up and eat us!"
"No more dump stories," Littlefoot said sternly.
"I'm telling the truth!" Cera cried.
Over Cera's protests Spike joined the group.