Where can i find cheap tickets under $200 to and back from houston to morelia?

Not to Mexico you won't. With 30 days advanced purchase, mid week you are looking at a minimum of $426 round trip.

To Mexico, no matter what the base fare is, you are looking at an extra $100 in taxes and fee's. Most round trips to Mexico are not below $300.

http://www.cheaptickets.com/
Or go greyhound.

try orbitz.com or cheaptickets.com or priceline.com

www.travelocity.com

Its $209.05 form Houston to Morelia on Greyhound. That is about it that I could find for you try calling different air lines such as Houston Hobby. Hope you have fun in your trip.

Let me know when you find one

I think depends in the season you go, in february i went to mexico city and for a roud trip from los angeles i'd pay 292.00 total and when i'd check prices in december where around 390.00 one way, what you can do is ask to a travel agency when is the season the tickets are cheaper. The other thing you did not said is if your going one way or round trip, for one way every 5 months i buy a ticket to guadalajara and are from 150.00 to 190.00
teotl15@yah