Hi Stagleton,
I am also a US ExPat living in Canada, but previously lived in England and I know what you're going though. Initially I had the pros doing this work for me too, but it was costing between $1000-2000/year. So in the spirit of Mustachianism, I eventually decided I would take it on myself, but it was very daunting because there are so many schedules to file beside the basic 1040 (3520,3520-A, 1116 (4 types), 6521,8962, 8891, not to mention all the FBAR stuff. If u decide to go for it, use the TurboTax Home and Business edition, most of the other programmes are worthless since they don't recognize for foreign source income and assets. Then you can take the last last return you filed (presumable prepared by an accountant) and use that as a template. Unless you do a lot trading, it should relatively straight forward. Once you do it a few times, it pretty satisfying doing it yourself, plus I found all these mistakes my accountant was making because these type returns are unusual for them too.
One final word of advise, which you probably know already, don't open up any Tax free savings accounts (similar to US Roth IRA) that aren't already recognized under US/German Tax treaty. This includes stuff for your kids like educational savings accounts. The reason is that these are considered by the IRS as a non-taxable trusts and they trigger the requirement of filing a schedule 3520 to the US treasury (not the IRS) as well as the schedule 3520-A. These schedules are not a part of Turbo Tax and must be filed separately from your regular return. Also they extremely complex and require knowledge of accounting to complete. So unless these accounts are huge and your saving many thousands in taxes every year, my recommendation is to stay clear of them as they are not worth the hassle and are the most likely thing to attract scrutiny from the IRS.
Good luck man.