Recently I got autocad 2009 installed in my computer but realized they installed it in Spanish. I want it to be in English, is there a way to change it to English??

There is no simple switch (yet). You can either buy a "Language swap" upgrade or just use the English commands in the Spanish version (start with the underscore - e.g. _SELECT _Window).
 
Here is a dictionary of EN-ES command names:
http://www.cadforum.cz/cadforum_en/command.asp
 

*sigh* I guess I'll just reinstall it.. thanks!