You can speak to th master of whispers or yourcular lord the chance to join you, usually tied to a fief. I find most lords join through defecting their own faction or being exiled. You can approach lords and ask for their support though to do this you should have a decent right to rule, be close to their fief for military defence, and be of a size that you could be appealing.

Robb Stark never joined my side even though we had a good relationship haha, broke my heart.

Same here, Ser Arthur, he never joined on my side, even though I pumped thousands of Stags into his coffers, and even helped in a few battles. He's a heart breaker, for sure, that fella.

But yeah, I think the best and most loyal lords you can rely on are the characters you recruit from the inns. After, say, a year of them being in your company you can give them a village or castle, some troops, and they patrol the area well, and loyal too. You can recruit at least 17 characters, that I know of, so grant them a little fief, and watch your power grow. They are handy when you send out the call to go to war.

Can your companions that you grant a village or castle recruit troops?
And thanks for the info!!!

Yes, they can recuit from their fief and the prisoners they free when they attack bandits or exile knights, etc. They stay strong, and always avoid stronger armies too.

I like having an ironborn army on my side, they are brilliant support troops!

I am Ironborn. They are excellent all round troops. Their Kraken soldiers are second to none.

Me to, always start with given some of my companions a fief (or more then 1) and that gives mostley pretty good results. Besides that, ones u are strong enough, other lords will come visit your main-town (where your stewards are settled) and like to join your kingdom aswell. (keep in mind that when they mislike you a lot, u can accept them as lord but better dont give them a fief.. they stay with you for a while and then there gone ;-)

Are the companions/lords you give fiefs keep up on construction and stuff of that nature?

Right to rule is a big factor as well