Since the people that answered before don't have Beastlord mains, I'll post my own answers and see if they prove useful...
1. Nothing new to add.
2. It seems to me, from this and other questions, that you might not have your Pet window up. I can't remember the exact keypress for this...but I do know that in the Options menu there is an option for this window to come up automatically when a pet is summoned. I believe that the default is ON, but if you turned it off at some point I highly recommend putting it back on. When you have the pet window up you will have most of the pet commands, including one for /pet back off. You can just spam this button to get your pet to come back...although if it gets hit on the way it will turn around to attack again...as you have seen. Also, if your pet is set to Guard, then it will move back to its home point much more slowly than if you have it set to Follow. So if it keeps getting hit, tell it to Follow before you tell it to Back Off. You really won't be able to do much about this until you get the /pet hold ability from the Pet Discipline AA ability, at a much higher level. So, as others suggested, pull with a spell or with a Throwing item, which is the only ranged attack Beastlords get.
3. At level 30 or so you get the Summon Companion spell, which lets you teleport your pet to you from anywhere in the zone, assuming it isn't fighting anything. So if you forget to tell it to follow, or if is taking too long to find you, then this can save some time. Or you can even leave it behind on purpose and then summon it later, if you like.
4. Again, if you have the pet window up you can see all the buffs that are on it. You will soon get some specific pet-only buffs that greatly increase your pet's damage output. You can extend the pet window to see all the buffs that are on the pet...I didn't realize that for a long time.
5. Magicians can summon some very nice pet gear that will benefit your pet very well. They add extra haste, hit points, and proccing abilities. Basically, pets are pretty smart, and if what you give them is worse than what they can do themselves, they won't use it.
6. Oh, man...there are so many things that Beastlords can do in a group. Since we are a Leather class, we don't tank as well as the Plate classes, but since we have lots of hit points we can do a pretty respectable job. In general we are just added DPS...and until the very high end of the game we are among the best. Don't forget that your pet hits more often when attacking from behind!
Because our pet usually has a quite large amount of hit points, and our heal spells are very mana efficient and don't draw aggro, we can be crowd control on multi-pulls and usually last more than long enough for the first mob to be taken care of.
The spells we bring to the group are also very useful. We get many of the same spells as Shamans, but at much higher levels. However, if there's no Shaman in a group, then something is better than nothing. Starting at level 22 we can Slow with Drowsy, which is around 15%. It only gets better, with upgrades at levels 50, 60, and 65. At level 65 we can Slow 65%, and I believe the max slow that Shamans and/or Enchanters get is 75%, so that's pretty good! We also finally get the ability to Haste others at levels 60 (Alacrity) and 63 (Celerity)...not a large amount of haste, but better than nothing if there are no other haste casters in the party. You need to be careful in a party, because casting your spells can get you aggro very easily. Sometimes this is a good thing--without Taunt, sometimes the only way to get a mob off of the healer is to cast a few spells on it and sit down and hope it comes at you.
7. Answered already.
8. The only times your pet will disappear are if it dies, you kill it (/pet get lost), you zone (rezzing and evacing counts as zoning in this case), or you turn invisible.
You might want to go to www.beastlords.org ...a good compilation of Beastlord-related material and a good messageboard there too.
Game on,
The Oneiromancer