That time of year

I need an accountant who is up to speed on writers'/artists' tax affairs, and in particular one who understands the intricacies of residence and/or obligation to file in more than one country.

I have been what I believe is called "domiciled" in Germany for several years but most of my income arises in the US; I am also a UK citizen which turns out to mean the Inland Revenue likes to be sent a tax return. I came over to the US last October and will probably be here through the end of May, having spent 4 months in Vermont, 1 in New Hampshire, 2 in Texas and 1 in a state yet to be determined.  I might spend the summer in the States (state to be determined) or I might return to Europe; I might go back to Germany or might go to the UK.

The agents representing Lightning Rods overseas say its foreign publishers must deduct 30% taxes at source unless I provide a certificate of tax residence in some other country.  I have been filing my primary tax return in the US all this time, but the forms relating to the relevant certificate don't seem to fit my situation.  It would help to talk to an accountant who understands these things.

I've asked for recommendations from various writers and artists I know; some say they are too poor to afford an accountant, so prepare their own tax returns; others have an accountant who is not really especially au fait with writers' affairs, or not especially au fait with expats.  It seems just possible that one of the readers of pp might know someone who could help; if you do, I'd love to know.

I have filed form 4868 for a 6-month extension, so the US return does not need to be turned around by April 17; it's more a question of getting things straightened out for the longer term and of providing correct documentation to foreign publishers. Again, if anyone has any good suggestions it would be enormously helpful if you could let me know.