Everyone will have a different method of how learning best works for them. I never put any time limit on it myself. During online play, I would play a session, then if I had a hand that gave me trouble I'd mark it.
After the session was over, I'd review the trouble hands and the biggest pots played that night in detail. I'd take those same trouble hands and post them on forums, getting other's perspectives. This type of learning worked best for me, and costs just your internet connection.
Personally, those programs you're talking about using like Holdem Manager or Pokertracker are a great tool, but not required. I'd highly suggest you aim to make that purchase if able, and if not, your first poker withdrawal should be to buy it in my opinion.
That being said, many high profile players like Phil Galfond for example, don't use a HUD, and live players certainly don't either! As long as you're making notes on your opponents about how to exploit them, you'll be fine. These programs will however make it easier to multitable, which really probably isn't best when you're learning anyway.
My suggestion would be to not bother with HUDs at first, instead focusing on playing solid TAG game, and making good, purposeful notes on opponents. Combine this with post-match hand analysis and interaction on poker forums
and you'll be well on your way.