Why do my nonstick fry pans 'bow up' and not make good contact with my flat top stove
The reason that cookware warps is that it is has too thin of a base.  When it has been heated to a high temperature, it warps upon cooldown.  The only way to avoid this is to buy very sturdy, heavy duty cookware.  You need to look for something with a very thick and heavy base, then you will have no issue.  

And don't think that it will put you in the poor-house.  I bought new pans 6 years ago, and they are still fine.  The most I paid was $30 for my 14 inch pan.  Every other pan I bought on sale for 10-15 dollars.

As for pots, you should be able to get a good set of Lagostina (or comparable brand) which are certainly not professional, but they will do the job.  They will not run too much money.

Just reread your post, originally missed the bit on the end.  You absolutely do not need to spend 200 dollars on a pan.  Just do your homework on the brand you are buying.  Where do you live (country, I mean.  Not trying to be too personal)? I may be able to suggest some places if you live in North America.