Graham
The main fault with your set-up is the directional tungsten light which appears too small.
You need to get some distance between the lamp and the light tent, and invest in a second lamp. I would go for two cheap contractor's lamps from ScrewFix, on stands.
These look great, or you could get two 500w doubles for �40 - just bear in mind power consumption and the heat tungstens chuck out. You'll cook yourself in a small room! Whatever you use, you'll have to make a colour correction on your camera or afterwards in Photoshop.
Assuming the size is OK, the light tent you have is OK, but there are loads of cheap and good ones on ebay.
But I have to say I'd be tempted to spend a few quid on the 180WS flash heads from the Far East, advertised constantly in ebay (see item 110104152296 currently). Get the double pack with stands and softboxes and you won't need the light tent AND have a much more versatile set-up.