A number comments have popped up to earlier posts by The Data Port, and even when they marked some level of disagreement with what's been said here they are a welcome addition to intelligent political discussion.
Here are some sources of reliable background information about candidates, issues, and finances.
Start with Project Vote Smart, a great site for reliable general info about the current political scene. (link) Move on to Open Secrets, the web site of the Center for Responsive Politics. This is billed as your guide to money in politics. (link)
And for fun, if you want to find out who your neighbors have supported with their money, and for how much, browse the Political Money Line. (link)
Finally, an annonymous comment has suggested that Gabrialle Giffords is a supporter of WalMart. Certainly not to my knowledge, so let's have a citation of sources for that claim. In the past Gabrielle has been supported by the S.E.I.U (Service Employees International Union.) It seems unlikely to me that any union would have supported a pro WalMart pol.