Can you just use electric tape for fingerboard tape?
or do you have to get some special type of tape?

I don't know if you can or not.. is it really sticky on the back? You do not want something that will leave residue, or something thats very thick. You can buy some for cheap..

http://www.swstrings.com/Store/Shopping.jsp?Category=Accessories&SubCategory=Any&Group=FT6

and off ebay..

Electric tape is usually not a very good sticker. There is lots of goo on it, but since it is intended to be wrapped it does not stick much by itself.

I would suggest painters tape. You can go to Home Depot, Lowes, Dixieline, or Frazee and get the blue painters tape. It is meant to be put on and stick to nice surfaces and then removed. If you do have residue when you remove it a littel rubbing alcohol and circular rubbing will do just fine.

I take it you're talking about marking out finger positions right? Personally I wouldn't use tape - it may be harder or take longer, but I think it's better to listen for the correct tone.. at least that's what my teacher had me do.

if you can go to a craft store and see if you can find thin gold tape, its not quite so "whoa" out there as white, and it is classy (should find it in the scrapbooking kind of section). but if you can't you can cut your own from the rectangular stationary stickers that you use to label stuff (the plain ones i mean) that way you can get them as thin as you like. but they are not long enough to go all the way around the neck so come off pretty quick. Paper stickers are the best (not shiny paper) as they come off relatively clean. nail polish remover will get rid of sticky residue, but be careful if you have an ebonised bridge, or a painted one, it might remove the paint. sometimes it is best to mark out the first finger positon (f# b e a from e to g string) and maybe the third finger postions as this way it gives you a guide but you still have to train your ear to the rest.