How do I read the account and routing numbers on a check?

See for an example here:
http://www.regions.com/virtualmedia/img576.gif

Bank of America checks look a little different. For more examples (including BAC) see here:
routing number check - Google Search (http://www.google.com/search?q=routing+number+check&hl=en&client=firefox-a&hs=vT5&rls=org.mozilla:en-US:official&prmd=ivns&tbm=isch&tbo=u&source=univ&sa=X&ei=qrNsTtXHLIHw0gH41-TyBA&ved=0CBkQsAQ&biw=1280&bih=605)

http://www.regions.com/virtualmedia/img576.gif

And of course if and when in doubt, call the bank they check is issued on.