I tried H&R Blocks free web based service. I gave up though because even though it said that it supported 2555EZ, it actually would only allow me to fill out 2555, which I don't have to do. Also, I couldn't figure out how to enter my UK employer's address. There was a box to tick for foreign employer, but it wouldn't work properly for me.
I also tried freefilefillableforms.org/, which is just the IRS forms presented in the browser. It does some simple calculations. However, I gave up on those because it can't handle negative numbers properly. On my 1040, my AGI was smaller than my personal standard deduction (after claiming my earned income on form 2555 EZ), and line 41 couldn't handle it, it wouldn't display my negative number. I emailed tech support, and they said that they replicated the problem, but that the numbers still come out in the end. That may be true, but as I can't see it, I'm not going to assume that the IRS can.
So, I haven't helped you at all really, sorry. Honestly though, give the h&R Block free version a try, the standard forms for us expats are there (1040, 2555, 1116), and you may figure out how to enter a foreign employer address. In fact, if you do, could you tel me how
Sam