Help!!! Can’t modify Header Information Error

http://www.jetshack.com
I am so new to this. I’ve tried starting out slow and to this point it’s worked out for me really well but I’ve come across an error that I can not figure out.
Warning: Cannot modify header information – headers already sent by (output started at /home/jon/public_html/index.php:2) in /home/jon/public_html/wp-blog-header.php on line 529
I’ve compared one of my index backups to my current one but
nothing pops out as unusual. I know it has to be there somewhere becuase
that’s the only file I’ve personally fiddled with. Once I noticed the error I did clean up my current index file a little bit, but nothing I did fixed the problem.
After taking a break from it be for a couple of hours while I went to the horse track I’m having trouble reproducing the problem and am wondering if it somehow fixed itself!
I first noticed the problem when doing a search. I used the term Hannah and the above error popped up on the top of the page. It didn’t have any ill effects other than just stating the error, the page continued to load. Now it’s not happening.
I would appreciate any kind soul who has a spare minute to run by my site at
http://www.jetshack.com
and see if they run into the problem. Maybe it is fixed. But if it isn’t I would love to know how to fix it!
I am using two plugins currently. Style Switcher and Exhibit and have made the changes necessary in my index.php that they required. I just installed Style Switcher and it’s been during this installation that I’ve run into the problem.
Thanks for the help.
Jon