To be able to play on Uldaris you can just download the LAUNCHER that will simply download the whole game ready for you, complete with all the needed patches.

Otherwise, you can also use any other Wow client (version 3.3.5a), just be sure to modify the realmlist like this:
SET realmList uldaris.net
You can find the realmlist.wtf file inside World of Warcraft – Wotlk/Data/enUS/ folder (enUS will change depending on your language).

You’ll also need to download the Patch-4.MPQ and put it inside World of Warcraft – Wotlk/Data/ folder, but be sure to remove any other patches from other private servers before launching the game (only patch.MPQ, patch-2.MPQ and patch-3.MPQ must be there). You don’t need to download any patch if you’re using the launcher.

The Uldaris Addon puts all of it in one window, reachable from the Guild Level button on your guild panel or with `/uldguild`. Guild panel. At the bottom of the guild window there is now an Unlocked perks line listing everything your guild has switched on. Guild window. Your guild’s level and experience, the three weekly bars with the gold each one pays, the weekly reset countdown, whether your guild owns a guild house, and your presence bonus shown as six ticks from 5% to 30% so you can see the next one coming. Two tabs: every perk, marked unlocked or still locked with the level it needs; and every achievement, marked earned or not, with the reward of the meta achievements spelled out. Appearance and gear.

The same addon replaces the old menus with a proper window:

• Appearance — transmogrification with a browsable, searchable catalogue filtered by slot, quality, item level and type.
• Enchants — put the glow of one enchant onto your weapon, main hand or off hand, without changing the enchant you actually have.
• Manage sets — save the look you are wearing, load it back later, ordelete it. Enchant glows are saved with the set.
• Reforge — move a stat on an item to another one.

Everything respects the same rules as the old menus: if you could not wear a look before, you still cannot.

You can install this addon as any other: just unzip it inside World of Warcraft – Wotlk/Interface/AddOns/ Folder