Hey, if you have their software and they say they'll accept a foreign address, then go for it! If all else fails, fill out your forms using their software then print out the forms and mail them in. This is sometimes necessary when filing from overseas if you can't meet some of their requirements for e-filing.
Download Publication 54 from the IRS site to get an overview of how your file from overseas.
Read on - your situation in your first year abroad may be different. Or not.
If you're working in the UK, you declare your salary income exactly like you would if you were in the US. The main difference is that you won't have a W-2 form. You may have to go back through your payslips (one of the reasons you are advised to keep pay slips virtually forever) to add up the salary you received in 2011. (The UK tax year is not a calendar year, so you can't use your UK tax documents for your US taxes.)
Most tax programs require you to "dummy up" a W-2 in order to add your overseas salary to what you earned in the US. Just fill out a second W-2 in the program, filling in only what you absolutely have to to get the program to accept it.
If she has no income for 2011, she won't need to file - and you should then file as "married filing separately." Fill in "NRA" on the 1040 form where they ask for your spouse's name and SS number.
You do have the election to file jointly for the year she left the US, but in that case you both are treated as US residents for the entire year - and you lose your foreign earned income exclusion (see form 2555 and Publication 54 for the details). She would also have to declare her entire worldwide income for the year (including any salary she has in the UK). It's usually not such a good idea.
Also, depending on the date you moved to the UK, you may need to hold off filing (by filing for an extension) until you have been outside the US for 12 consecutive months. (Again, Pub 54 explains all.)
Cheers,
Bev