Anyone know if I can get this to work on windows 7, also does anyone know where I can buy this online?

You can't buy it anymore because it is replaced by Command and Conquer Collection.
You can buy it on Origin http://www.commandandconquer.com/collection/

The First decade pack got a 1.03 fan patch and several smaller patches for the older games and all can be run without problems.
Check out the official EA C&C support forums for those.

If by any chance you weren't meaning online as online digital version only, you can still buy the first decade in a retail DVD box, very cheap, through Amazon.

Walmart still selling it for 14.99. It's not a digital download though. All the games install on the computer and you don't need the dvd in the drive once installed. I am running windows 7 64 bit and the games run fine ... I think the earlier games in the series have that Rainbow color effect in the menu but can be fixed using various methods that solve the same problem with some other older games like Starcraft.