what can I do?

What is the name of your state? Arkansas

I purchased a used vehicle on 11/10/03 for 2500.00. The agreement is as follows: I paid 1600.00 down and pay 200.00 a month untill I pay off the rest. He gave me a 30 day warranty on the truck. The truck has bee in the shop twice since I purchased it for 3-4 days at a time. I had to pay a 200.00 towing bill and paid for taxi rides to work the days my truck was in the shop. This last incident he wanted me to pay half the cost of repairs to the transmission (the second attempt to repair transmission problem.) And he has not paid me for having the truck towed or for transportation to work. What can I do? Since the warranty expires 12/10/03?

Tell him no, he either pays for the entire repair as per the warranty, or he can refund your money and sell this lemon to another sucker.

By the way, unless your warranty specifically states that towing and taxi rides are reimbursable, they are not.

But wouldn't taxi rides and towing fees fall under Incidental charges or is that only if I get a refund?