If you also posted on Facebook, I thought you meant you had bought one of the later boxes with a portion of a Space Marine army, rather than the game itself. The two editions had different quantities of marines, but either way you've got the basics: tactical squads, rhinos, and land raiders.
Keep in mind that that infantry and Rhinos are quite small compared to the third-party stuff that's out there. But that's where you'll have to go...
This is where you can find proxies for Predator Annihilators, Vindicators, and Whirlwinds. The Athenas are female, but less obviously female than the ones in tactical-like armor, so cut the hair off and they could work for Terminators.
http://vanguardminiatures.co.uk/product ... isterhood/Any of these with "Elite" in the name are pretty obvious Space Marine proxies. Affray Heavy Armor are a good buy because Terminators are great. The Bulwark will come in handy as a Thunderhawk, the Skimmer Wing as standard Land Speeders, Quad Bikes as bikes. The assault marine look-alikes are less important because the unit isn't widely loved in terms of the rules, but they're very nice models. The specialists are more useful, imo. The Trojans are meant to be Rhino proxies but they're much larger than the old plastic ones.
Among non-Elite Novans, the Rorqual might serve as Spartans (a bit big), the Marksman as a Shadowsword.
http://vanguardminiatures.co.uk/product ... ulum-nova/Go on eBay and find the trolls.cz store. They have Basilisk and Medusa proxies, which Horus Heresy marine armies can use.
Litko for blast markers.
