'Micro' covers a lot of ground. What sort of equipment are you going to use, and where are you going to fly? Those two items would help with more specifid suggestions.

Here is a link to the documentation for the RFFS and the Skeeter airplane for it. It is a simple as it gets. They even make laser cut kits if you want. http://www.smallrc.com/DWEHtml/documentation/RFFS-100 revb instructions.pdf

RC Micro Flight has some free plans for mid-sized micro indoor/outdoor flyers at http://www.rcmicroflight.com/ - look under sample articles, DOwnlaodable plans. The original 'Tiny', 'Pond Baby' (a flying boat), a Bellanca Biplane, etc.

If you want to try fan fold, hippo's website has a bunch of 3F plans that will fly indoors. Go to http://www.foamfly.com click on 'photo gallery' and find a link to 'Glen's free plans'. Planes cost about a dollar in materilas to build.

These are just some starting points.