David Gemmell was pretty unique as an author, and it’s not easy to find good quality books that are similar to his. However, there are authors which write good quality stuff which share some aspects of David’s books, so if you enjoyed Gemmell you might well enjoy the following authors / books.
James’ Raven series share their action packed nature with Gemmell’s work. They’re quick paced with plenty of combat played out by interesting characters. James can be found here, and you can read plenty of information about the Raven books by starting here (and scrolling up!)
If you liked the historical fantasy side of David’s work, you should check out Conn’s historical fantasy books. At the time of writing they are his Emperor Series and Conqueror Series. You can check out information about the books on Conn’s website (and specifically the first Emperor and first Conqueror books).
Stan’s has written one series and is working on a second series of books about a fighting band of Orcs. While they have a more obvious fantasy slant than David Gemmell’s work, they are also gritty, fast paced and action packed, with plenty of humour to break up the combat. You would do well to take a look at them. You can find Stan’s site here.
If you have any other authors or books you feel would be enjoyed by people who loved David Gemmell, feel free to comment on this article with your recommendations.