In my weekly email from the Michigan Coalition for Responsible Gun Owners:

Myth: The availability of guns causes crime. -- Fact: In 1968, the U.K. passed laws that reduced the number of licensed firearm owners, and thus reduced firearm availability. Their homicide rate has steady risen since then. "Criminals are not motivated by guns. They are motivated by opportunity. Attempts to reduce public access to firearms provide criminals more points of opportunity. It is little wonder that high-crime cities also tend to be those with the most restrictive gun control laws - which criminals tend to ignore". -- page 24 of Gun Facts 4.2

Gun Facts 4.2 is a free 96 page reference guide to gun control issues by Guy Smith.