High gain, directional wifi antenna, mounted on motors (probably knock something up with meccano) and stationedx on the roof, with a switch close by to run the wire into, which then feeds the signal back to you (if you used an overly long wire to plug into it without using a switch to break it up, the signal would be useless).
Shit, if you're going that far, have one rigged up to a satellite dish.
I've only played Terran Conflict (the one I have over 500 hours on) and playing Albion Prelude now, so I can't really speak for them all. I'd say those are the two main ones out of that lot (they are the two most recent too).
If you just want to try one for cheap, by all means just pay a dollar and get the set that includes Reunion. Sure that's a good game too.
Biggest tip I can give you - as soon as possible, get a ship with at least one non-player controlled turret (usually at the back) and fighter software mark II - this is so you can set it to missile defense. Nothing worse than hearing "Missile closing" and not being able to find the fucker fast enough and being blown out of the sky.
The learning curve on that game can be steep...but fuck is it worth it.
At the bottom of the page. I've always bought from HB using paypal.
Jut where it says how much you want to pay, enter $6 (you won't get all the games unless you beat the average) nad stick in your email. If you really want, you can give a false email as once you've bought it it takes you to a page with the codes on.
Oh, you've never used Steam. You're going to need a Steam account. It's no big deal, takes about ten minutes to set up.
It's very engrossing. I've racked up over 500 hours on the Terran Combat version in the last few weeks. Started on Albion Prelude now. It's tough to start from the bottom all over again after being a billionaire captain of industry and pirate terror to all factions (I don't even buy capital ships any more, just steal them and reverse engineer), but the addition of the war is a lot of fun.