The original game had over 400 factions, if I recall correctly. It's pretty hard to give an idea of who hates who, as some depends on race, some on diety, and some on what which NPCs of a place you are talking about.
But in general. Iksars hate everyone, and everyone hates Iksars to start with. Vah Shir and Drakkin are Indifferent (middle of the road) to everyone. I'm not positive that the reverse is true for either of those. Wood Elves and Dark Elves hate each other, and as far as I can tell, you can not get a player of either race to be liked at all by the other without becoming KoS (Killed on Sight -- Max hated) with their own people.
The Evil races are:
Ogre, Troll, Iksar, and Dark Elves
The Good races are:
High Elf, Wood Elf, Halfling, Half-Elf, Dwarves, and Barbarians
The Neutral (or can go either way, depending on race) are:
Human, Drakkin, Vah Shir, Gnome, Froglok, Erudite
Your diety plays a big part in faction also. The way the game is done currently though, faction plays very little part in being able to do anything, but certain old-world quests, the large majority of which aren't worth doing anyway, and haven't been for a long time. Most likely, the only thing you'll want to check faction for is for your toon's epic quest. But even, if you screwed it up along the way, you can generally fix it, unless you have went out of your way to mess up faction with your race, class, and diety. Generally this would involve killing NPCs in the cities of your race and/or allies to your race.
Anyway, with the advent of Plane of Knowledge, the one zone that connects to so many other ones, faction is not really an issue, since you don't have to run through lots of zones with KoS npcs.
Also, when creating your new toon, read the descriptions for the race, class, and diety. Picking what suits your play style is way more important than worrying about how well you get along with other races / classes. However, the Iksar is a fun race to play, just because everyone hates them, and they hate everyone, so is more challenging, or was back in the day, when trying to figure out how to get from point A to B, and how to be able to buy / sell needed goods when far away from home. Now-a-days, that's not a problem at all.
Hope this helps.
Yther Ore.
BTW: You should read the sticky for New / Returning players, many of your questions are most likely answered there.
Edited, Apr 25th 2007 2:40am by Yther