So I bought this old bike but realized that its seatpost is stuck and high. When I ride I feel uncomfortable because it's slightly too high for me. Also I realized that it's really difficult to fix the stuck seatpost. Is there a trick that could help me work around this problem and make me feel comfortable when riding the bike?
Sheldon Brown has a thorough article about stuck seat posts. http://sheldonbrown.com/stuck-seatposts.html
Thick soled shoes might also work, if the saddle isn't that much too high.
If it's a steel frame some people recommend heating up the seat tube (LIGHTLY) to expand the metal and then try and wiggle the post out but that seemed like too much effort to me.
When I got a seatpost stuck in a frame I went to an auto garage and put the frame in a vice. Then used their pneumatic air chisel on the seatpost and it came flying out in seconds.
If you go down that route, it might be an idea to give some money/beers to garage as a thank you for using their kit.