Trumps of Doom by Roger Zelazny is one of the books in the Amber series and is the first book of the second series. It is definitely not a stand-alone and requires the next books to complete the story line. It won the Locus Award for Fantasy in 1986.
from the back of the book:
Merle Corey is a brilliant young computer designer in San Francisco. But he is also Merlin, son of Corwin, vanished prince of Amber-heir to his father's wondrous powers-and someone is determined to kill him. Now he will begin a desperate race through Shadow to escape the mysterious force that threatens his life... and to protect the deadly secret that could destroy both his worlds.
I've read Nine Princes in Amber, which is the first Amber book, and liked it well enough but not enough to continue the series. #2 Son said that the first book was "ok" but thought the tie-off at the end was a bit neat and quick.