Sergey Lukyanenko's The Watch Series

Sharp observational writing and a predominantly Russian setting give this modern-day set fantasy series, in which good and evil have settled into an awkward truce, wider appeal than most genre fic.

If you know any teens settling for Twilight, these ought to come as a revelation.

[The Night Watch] [The Day Watch] [The Twilight Watch] [The Last Watch][The New Watch] [The New Watch]

A couple of other short tales set in the same universe, Face of the Dark Palmira and The Other Among Others have been written by other authors, but currently the only way you're going to get them in English is to make do with bad auto-translations.

Material from the first book was adapted into the excellent films Night Watch and Day Watch.