If you are into your nails (I started last Christmas lol), it might be worth trying a couple of China Glaze polishes as well (Sallys here & USA sell them, also on ebay US - someone sells them buy 2 get 1 free, but you pay p&p on them all). China Glaze have a nail strengthener in them, which I think may be helpful as well.
Also found it useful to cut nails rather than file them even when using a glass nailfile, I am sure filing seems to split them. Invested in a pair of Tweezerman scissors, as they cut nails well, rather than 'squeeze' them which bluntish scissors seem to do.
Also if you go to makeuplley.com there is a nailboard forum on there. The people there are really helpful for tips relating to all things fingernails & toosties.