Genii is a pretty good magazine, with a fair amount of card effects in it. Some of my pals have got some really good material from it. I personally prefer "Magic" magazine. Not really a lot to distinguish the two, I just prefer the layout and style.
If you can get hold of it, and thats a big if, Jerry Sadowitz produces a very high quality publication

called "The Crimp" I have got a few copies and although initial thoughts are "what on earth is this" It is nearly solely devoted to card effects albeit with a small amount of mentalism. And the effects within are awesome. They are not self working, and will require you to practise a lot, but I have had very strong reactions to anything I have got from "The Crimp"
Have a look on ebay if that is easiest as there are often editions for sale. The magazine also includes Jerrys robust humour. Not to everyones taste, but there you go.