Hmm, if you just look for a tile based game tutorial, then you can easily convert it to a platformer.
Search up the video tutorials on
http://www.nickontech.com/2008/09/tile-engine-series-new-home/, they teach you how to create a 2D tile engine, so that should help you understand more about storing maps and what not. I used them to create my own tile engine and am now using it to create a platformer also.
Basically its like a 2D tile based game except, if there is no tile that you can stand on directly below your character, apply gravity to the character.
For example, the maps would look something like
0 0 0 0 0
0 0 1 1 0
1 1 1 1 1
And if the poition directly below the character is not a 1 (1 would represent a solid square, 0 would be background or w.e), move the character lower..
Sorry if the post is a bit random or confusing

, but if you have any questions just ask..