Tools for DIY Wedding Planning?

Reader Mike just got a “yes” from his girlfriend in reply to The Big Question, and now he’s looking ahead to The Big Event. Being a regular reader, a frugal guy, and an “addictive planner,” he writes seeking help:

Do you have any suggestions for software (I use Windows, BlackBerry, and Windows Mobile platforms) that I can use to keep track of vendors, quotes, and other sundry details?

Having tied the knot less than a year ago, I found some success using Google Docs for multi-user planning, but also spent a lot of time explaining its features to everybody—and ended up losing a few invitations to accidental deletions.

So I turn to our wise readers and ask: What software or organizational tools would you/did you use to plan a wedding, covering as many aspects as possible? How would you keep on top of your tasks, decisions, and deadlines? Give Mike an early gift of advice in the comments.