if you want to play COH2 with a friend, yes it is by steam only.
If you want to play with random ones, use the online menu =)
About the tournaments i can't respond to you.
Hope it helps =)
I am just an average player, but let's talk about balance on 2v2(i know in those forums your more interested by 1v1 balance) :
I am generally called noob when i loose as soviet(and actually i loose a lot), but 70% of players look for a game on the german side. Why ?
In allmost every departement of the game german are superior to soviets on 2v2 games :
Except the very early game, germans have hard counters to soviets:
1/ Bunkers and mg's : in team games if they cover well each other you need a M3 with flamers to deal with them. The survivability of this thing is really really low.
2 / T2 german rush : Flame halftracks/scout cars are a pain to deal with, guards are only a soft counter to them. It takes ages to build T2 building to get an AT gun. So going for snipers is very risky. Ostwind is insta retreat oftenly.
3 / Combined arms = as state above it takes ages to build the T2 building. So going for combiened arms takes so long your generally on the defense or germans have locked down key positions.
4/ T3 : T34 can't face panzer 4 on their own. You need 2 of them to get a Pz4. due to german superiority very early it is very hard to deny them the fuel to be faster than them. German T4 owns badly T3 soviet.
4/ T4 : SU 85 shoots well, but again german have hard counters easily. Panzergrenadiers
spam is very common on 2v2, they wreck SU 85 very quicly. Non upgraded with panzershrecks they eat conscripts really fast too. A vet 1 german tank can rush you easily and outmanoeuver you easily too. Again you need guards to hold them.
I won't even talk about elephant which deny very large portion of maps to all your tanks. You just have to have a ostwind or a few pg near it and you have locked all tanks and infantry of the soviets.
So the best way is to get a combined arms army (guards soft counters to vehicles, very long times to build buildings)on the soviet side to be able to manage allmost every stage of the 2v2 games an endless hill, unless you really outplay your opponents.
Please refrain the flame and lets discuss about solutions to have a well balanced 2v2 game.(sorry for my bad english)