There are several ways of getting higher attack levels on Runescape. The most common way is to just train on monsters. Although training on monsters is probably the most known and considered the easiest way, there are indeed other ways. For members, there is the mini game of Pest Control. In this game, you fight bugs on an island with your team. If you achieve a certain amount of points while fighting, you will get some points afterward, which you can use to get items. The points while fighting are calculated by your hits. If you hit a 5, you will have 5 points. If you hit a 10 after that, you will have 15 and so fourth. I believe the goal is 60 points or more. More is always better as the more you get the more points you will get back on the island. To get to Pest Control you will have to take a ship found at Port Sarim. It is a fun mini game and is very good with raising your attack, though I do not recommend it for lower levels.

For Lower levels, training is probably the best. You could also do some quests. Quests will sometimes give out experience points as a reward. Though remember, these can take a long time and you could have spent the time it took you to do the quest in training and gotten more levels.

If you decide to train, there is really no basis for it. However, of course there are "recommended monsters", but this is not to say that they are to abide by at all times. When I was raising my attack to 60, I spent half of the time fighting goblins. (Yes the level 5 goblins up at Goblin Dimoplocy.) These gave quick and easy exp. In the time it would take me to fight 1 high level monster with food, I could kill like 25-30 goblins without food. Eventually I went into the
Stronghold of Security and killed the level 13 goblins, and then moved onto Minotaur which gave me that extra boost to 60 attack. Therefore, as you can see, there really is no basis.
If you were to train, it's a better idea to train on lower level monsters with more exp than higher-level monsters with less exp.

You might even want to bring a friend; it will help keep the boredom down.

There are many other ways to get higher Runescape attack than what I just mentioned. There are other mini games to offer you more attack experience. You can get experience in Castle Wars, or the Duel Arena. The Duel Arena is good if you have a friend. Then you can fight them a bunch of times. Many times you can find people willing to let you train on them inside of the Duel Arena hospital, though a lot of people are there to duel and not get killed, so don't get your hopes up on some stranger. Its better to ask your friends.

You could also train inside the Fight Pits. I really like to train there as the scene looks cool, and it gives some good exp.

Now, that you know a little something about how to get higher attack on Runescape, Why not go out there and try it? What have you got to loose? Well I suppose if you die you could loose some good items if you were skulled and carrying them, so don't go training when your skulled.
Then you won't have anything to loose. (Unless you carry more than three items.)

Don't be afraid to loose your items, because if you do loose them, you can always buy some more. Now, don't start complaining about being poor. You can always beg on the streets. Alternatively, go fishing, mining and so on. (On the other hand, even go pking when you have a higher attack.)

Happy Playing! (Erm, training I mean)