With an endlessly changing and varied profession, such as taming, there is an equally endless list of questions asked by newer tamers. Hopefully, I answer a few of your questions here.
There is a 2 part guide specially geared for those just starting out. The first part is specially designed for newbies to UO and talks about renaming, feeding, and commanding pets. If you're just plain new to taming and are familiar with all of that, the second part is right for you. It glosses over what to tame, as well as some pet quirks and a little about adventuring.
Try the What do I Tame?? script. It will tell you exactly which creatures are right for you, including pretames.
Skill gains are relatively similar in all skills. They start out very easy to gain and gradually get harder and harder. If you're taming a variety of creatures within your target range as generated by the What Do I Tame?? script, there's not a lot that can be done for you. Complaining about not gaining taming at XX.X skill is not going to make it go up any faster. There is no special technique to make skills move any faster. Only by working on the skill will it ever have the chance to move.
GGS gains are something different altogether. Unfortunately, even with this system in place, there is still a random element to skill gain.
You must be able to control the creature before it will be willing to transfer to you. You can use the Control Calculator to determine if you can control the creature. If the calculator returns 0, then the pet will not transfer to you at all. You would need to have 70% control or better to have a reasonable chance of controlling the creature, and even then, it should not be done in a high spawn area.
There is a special exception to this rule, and that is with creatures that have no orneriness. They can transfer and bond to anyone, regardless of skill.
Animal lore does 3 things for a tamer: aids veterinary for healing, lets you see various information about the creature (skills, stats, loyalty, etc.), and allows you to control your pets. Having low animal lore will not make taming any particular creature more difficult, nor will having high animal lore make it easier. Only the taming skill is checked when attempting to tame a creature.
Pets resurrected by their owner or someone who is friended to them will take a certain amount of skill loss. A pet resurrected by anyone else will cause the pet to take twice as much skill loss. The higher the pet's skills are before its death, the less skill loss it will take. You can determine what your pet's stats will be after resurrection with the resurrection calculator.
There is no one skill set that's required for being a tamer. What you choose should be based off of your play style. Check out the most popular skills used as a tamer to help you make your decision.
There are many good regions of Britannia to tame. I have documented and mapped out a few regions under faqs for taming hot spots. Once you know what to tame for your skill level, try to find a spot that has creatures that you are looking for.
Check the tameable chart. Almost everything you could wish to know about an animal is found here.
While attempting to tame a creature, it must not take any damage (physical/magical attacks, poison damage, or paralyzation). Once it takes damage, it will become too angry to continue taming.
Nothing. This is supposed to happen to make the high end creatures tougher to tame. You will only successfully initiate taming on dragons, swamp dragons, nightmares, and white wyrms approximately 1 out of 10 tries.
Pets never lose stats. Ever. Pets only lose skill the first time it is tamed and every time it is resurrected. Pets lose 10% of their skills the very first time it is tamed, but 14% if they were paralyzed when tamed. Highly trained pets lose less skill than pets with low skill when resurrected by the owner or a friend. If a stranger to the pet resurrects it, then it will lose double the amount of skill it would have lost if the owner or a friend had done it. At 100.0 skill, the pet will lose 1% of its skill upon resurrection, or 2% of a stranger resurrects.
Read up on pet training. There is no difference in training different types of pets. All pets raise magery the same, all pets raise wrestling the same, etc. The only difference is that you need to find creatures to train your pet against that won't kill the pet.
Pets can only learn skills that they use (a frenzied ostard can never raise magery, because it doesn't use it). In terms of skill levels, they have the same 0-100 skill system that players have, as well as receive stat bonuses for skills like players do. If the pet has less than 125 in a stat, then it can be trained to 125. If it has greater than 125, it will never raise unless blessed in some way.
No. Creatures from a champion spawn are like those from a camp spawn and will disappear after a certain amount of time, regardless of whether or not it has been tamed.
If you are a previous or current owner of a particular creature, you can retame the creature with no skill difficulty. If you have never been the owner of a creature, then the retame values apply accordingly. There is no change in orneriness post Publish 16.