Check out RCKen's list of trainers he has assembled. This should give you a good start into researching the various planes available. Since nitro flies a lot different from electric, I would recommend getting with a club or flight instructor to see what trainers are popular in your area and getting some dual instruction. Your chances of success will be a lot higher with a flight instructor to guide you along on your first few flights.

Here's the link to RCKen's list:
http://www.rcuniverse.com/forum/m_4537845/tm.htm

Hogflyer