As previously mentioned Monster is your friend, a lot of agencies use it and I got my most recent job through there.
Not sure if MCSE will do much for you at the moment if your only experience to date is in building PCs though.
Perhaps some self-employment would be in order, advertise your services troubleshooting and repairing PCs to people, undercut PC World a little bit
Might not make you rich but will give you the experience you absolutely need, at the moment you're competing with graduates and sadly A+ and Network+ don't mean that much.