Some useful links about Flash and tile based games:

OutsideOfSociety. Grandfather of all tile based Flash games.

GotoAndplay has many useful articles about Flash games.

metanet. Creators of famous "N" game have been very nice to explain the advanced physics and collision system behind the game.

Flash games tutorials by Emanuele Feronato. Lots of game types introduced, not just tiles. With code, good explanation and source files.

Tile-based Games. Lots of articles about tile based games. Nothing about Flash there.

Game Programming Information. Huge collection of information, has many articles about tile based games.

Interesting idea from Strille. Explains how to use tiles/objects of any size in free position.

Isometrics in Flash written by Senocular. Series of very good articles about isometric view and how to implement it in Flash.

bit-101. Check the tutorials about gravity, easing, perspective and elasticity. It has also thousands of examples in the Laboratory section, many with source fla available.

The Designer’s Notebook. Very good articles from Ernest Adams about game design.

Mappy is utility for creating flexible maps for tile based games. Can save 2D arrays for Flash actionscript. Windows.

ArrayPainter has been created specifically to make 2D map array fast for Flash.

Translations:
Tile based tutorials translated into chinese by qhwa.
Tile based tutorials translated into french by Julien Labeaume.
Tile based tutorials translated into russian by Igor Semykin.