Get there early...
I took my 2 young children to the Blue Bell Creamery yesterday (4/5/10), arriving at 1:30. There were no parking places in either of the 2 lots, and I had to drive around for 15 minutes waiting for someone to leave. When we got in, we were told the 2:45 tour was the only one available. The gift store was open, but full of people, and there were very long lines waiting to buy ice cream for $1 a scoop. Every few minutes, a group of about 30 would be ushered into the same line to receive their free scoop. (The dedicated tour ice cream shop was closed). The tour itself was fun and informative, but not quite worth the $5 per adult price of admission. I suppose they raised the price to from $3 recently to keep the crowds down. It hasn't worked so far.
Overall, a once in a lifetime experience... not something I need to repeat.