Hello community! I am still relatively new to the game (level 7) and I've been doing solo the most (only 3-4 premade games). I would consider myself a pretty decent player in compared to those in my level bracket. I know a few good builds for different characters, have pretty good ganking abilities, and will usually go +2-6 in my fair (full 5v5 / 3v3) games.

However, I find that in the majority of my games, there has been a person who ragequits on my team, who dc's or who is just afk for most of the game thus making it much harder for my team to win. Therefore my record is pretty bad (5-12?) most of the losses from quitters.

Is this common for my level or am i just getting really unlucky? Are there any ways to combat this and maybe win sometimes?

Yes, it is common at the ELO bracket you are in, and part of it is also luck. When you rise up in ELO this will happen less often. What you can do is befriend those you played with or against whom you think were good players who had good attitudes. Queue for games with them, and it will greatly lessen the chance of you getting teamed with a leaver/afker.

If you have a leaver/afker early game, your team can still potentially take advantage of your level advantage (since there's less people sharing EXP), group up and push to win while you still can win fights due to the discrepancy in levels. Once the enemy team catches up on levels, it is unlikely you'll be able to win.

Seriously if you aren't adding the teammates and enemies you play with or against who are friendly talkative and who you think play the game well to your friendslist you are making it so much harder on yourself to find good games.

yeah you really should just kinda add everyone who seems to have a good attitude and plays dec,
P.S. kinda on a side note, but i just played a game where we had 2 afkers adn my premade of 3 still won So it pays to make friends with good players on your team

If i ignore a user, does it mean that I wont be playing them in future solo games? I hope this is so, coz I have been ignoring so many people who just rage quit or are AFK for half hour, its really taking the pee. Most of my losses are because of this as OP said.

Also, I saw something about Queuing for game with friends??

So say I befriended a person, I can queue to play him? Whats this? Or do you just mean like wait for him to fininsh the game and the Private chat him to set up a game....

You can queue up with someone you added by going to arranged team when you select the map you want, or in practice games there is an invite player button that you can use, all you need to do is select the friends you want and hit invite.
As far as skipping those you ignore, Im not sure but I think you avoid them completely from that point on.

Ignore does not prevent you from playing with someone or against them. It simply mutes the person and prevents them from sending you invites for anything.

I suggest you report the leavers/afkers at the end of the game by right clicking on their username, you can also ask the enemy team to do the same. Multiple reports tend to garner quicker responses on bans on Riot's part.