Michelle, even a 39 bucks tripod would be 'rocksteady' during exposures, long or short, on a windless day and using the selftimer like you described you did. If the prob is movement, something else is doing the moving! Not the tripod.
And what scoundrel say sounds good: post some samples, or send them, and let others have a look at them. Could reveal a lot.
With
http://www.yousendit.com/ you can – how'd you guess? – send huge files. For me, on OSX.3.9, it works best in FireFox.