[QUOTE=Lissla Lissar]
And Guy Gavriel Kay lives in Toronto and Charles De Lint is from Ottawa. Oh, and Tanya Huff (must order the Blood series) used to work at my favourite science fiction/fantasy bookstore, and now lives in Kingston.
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Robert Charles Wilson, already mentioned, is the best Canadian sf writer, BTW. Nalo Hopkinson, from Toronto, should be mentioned, along with Julie Czerneda and James Alan Gardner also from Ontario.
Dragon Moon Press (http://www.dragonmoonpress.com/), along with Edge and Tesseract Books (http://www.edgewebsite.com/) are the leading Canadian small f&sf presses.
A page of Canadian f&sf links.
Some British writers that may be easier to obtain and/or better better in known than the U.S. include M. John Harrison, Geoff Ryman, Charles Stross, Iain Banks, Ian Stewart, Ian Watson,… heck just stock anyone named Ian. Cory Doctorow is American but living in England these days and he’s become well known because of his Boing Boing blog. I think Neil Gaiman is the reverse, now living in the U.S. but he sells even better.
Neil Stephenson started in sf and his latest work is on the Venn intersection of fantasy, sf, and mainstream, but is wonderful and sells like crazy.
Leading small presses in the U.S. f&sf world include Wildside Press (http://www.wildsidepress.com/), Meisha Merlin Publishing (http://www.meishamerlin.com/meishamerlin.html), Tachyon Publications (http://www.tachyonpublications.com/), and Small Beer Press (www.lcrw.net/) - which is run by Kelly Link, the best short story writer working in the field today. The first two have mostly straightforward f&sf; the latter two are at the more literary end of the field.
All are good places to go for working writers. You should have some of the dead white men classics, of course, but support for today’s writers means there will be a future for the field, and future classics to stock.