Space combat is a massive departure for me from my normal gaming activities. Moving from Roman legionaries to Vargan Battlecruisers is a pretty big step by any stretch of the imagination. The rules we use for our space combat are a modified set of  ‘Space Cruisers’ by Warp Spawn Games and available for free from the ‘Free Wargames Rules’ web site or direct from the lovely people at Web Spawn Games.
The ships we command, without the style and skill of James T Kirk, are the absolutely gorgeous Dreadnought 3000 range from Kallistra Games of Mansfield, just down the road from where I live in Nottinghamshire.
There are a few pictures of my first attempts at painting Dreadnought 3000 ships here and all the links you need to get your hands on the rules and the ships.

An Earth Empire Battlecruiser, supported by a pair of Patrol ships, close in on a Vargan Battlecruiser and its destroyer escort.
So far, even though weaponry is largely randomly generated, the Earth ships have easily outclassed the Vargans. Perhaps this has something to do with the fact that son Tom (aged 10!) has been in command of the Earth craft whilst the poor old Vargans have had the old duffer in charge.

A close up view of the Vargan destroyer and the Earth Empire Patrol Ships. All the ships are available individually from Kallistra, but we bought ours as part of a couple of fleet packs at £11.95 each. Good value!