Help me pick out some good d20 products

[Greatwyrm]

If you DM much, I heartily recommend Monster's Handbook from Fantasy Flight.

Monsternomicon from Privateer Press is very good. Find the 3.5 version if you can.

I've heard very good things about DMGII, although I don't personally have it.

 

[Psion]

A quick selection; filter to taste.

Arms & Armor v3.5 (Bastion Press)
Wildscape (Fantasy Flight Games)
Portals & Planes (Fantasy Flight Games)
Advanced Bestiary (Green Ronin)
Advanced GameMaster's Manual (Green Ronin)
Complete Book of Eldritch Might (Malhavoc)
Denizens of Avadnu
Beyond Countless Doorways
DMs Directory of Demiplanes
Hyperconscious (assuming you already have Expanded Psionics Handbook. If not, get that first)
Races of Stone
Complete Adventurer
Ultimate NPC
Eldritch Sorcery (if you are into spells)
Book of Fiends

 

[Ed Cha]

Well, it's not so much rules, but the Penumbra Fantasy Bestiary (Atlas Games) MSRP $45 is on sale right now for only $15!!!

Check this thread out for more information:
http://www.enworld.org/showthread.php?t=142388

Another great monster book on sale is Denizens of Avadnu (The Inner Circle). It's an all-color, well-written hardcover book priced at $31.95 (20% off of $39.95).

Also, the recently released Dawning Star (Blue Devil Games) is available for a special sale price of $19.95 to celebrate its ENnie nomination as Best d20 Game. Poisoncraft (Blue Devil Games), mentioned earlier, is also a good bet especially since it's on sale, too, for $12.95 (25% off). Lots of great poison rules.

 

[Romnipotent]

Just for the art (apparently, Im buying these too soon) Allies and Adversaries as well as Friends and Familiars from bastion press

 

[Ghostwind]

A quick look at the Bastion Press online store shows the following 3.0 edition books marked way down...

Airships $14.95
Alchemy & Herbalists $14.95
Allies & Adversaries $5.00
Faeries $17.95
Friends & Familiars $5.00
Guildcraft $14.95
Oathbound: Plains of Penance $17.95
Oathbound: Wrack & Ruin $15.95
Pale Designs: A Poisoner’s Handbook $14.95
Spells & Magic $14.95

Most of these are at least $10 off the original price...

 

[The Shaman]

d20 Modern and the Modern Player's Companion - just say no to fantasy.

 

[Pants]

Here're my suggestions:

Monsternomicon 3.5 by Privateer Press
Alchemy and Herbalists by Bastion Press
Frostburn by WotC
Complete Adventurer by WotC
Expanded Psionics Handbook by WotC
Dungeoncraft by Fantasy Flight Games
Portals and Planes by Fantasy Flight Games

 

[Psion]

A quick look at the Bastion Press online store shows the following 3.0 edition books marked way down...

These are very good, IMO:

• Airships - Just started using this myself
• Alchemy & Herbalists - Cool stuff in the right kind of game.
• Spells & Magic - Some great ideas for magic. Two cities in my game are based off of ideas herein.

 

[philreed]

These are very good, IMO:

• Airships - Just started using this myself
• Alchemy & Herbalists - Cool stuff in the right kind of game.
• Spells & Magic - Some great ideas for magic. Two cities in my game are based off of ideas herein.

I'll second all three of these.

 

[Edheldur]

For good rules expansions that build upon the existing d20 rules or complement them nicely, my suggestions are:

* Wildscape (Fantasy Flight Games)
* Portals & Planes (Fantasy Flight Games)
* Cityworks (Fantasy Flight Games)
* Dungeoncraft (Fantasy Flight Games)
* Book of Iron Might (Malhavoc)

I particularly second all of the above suggestions.
Wildscape has some great terrain rules and has seen heavy use in my campaign.
Portals & Planes can be used on it's own or as a compaion for WotC's Manual of the Planes.
Cityworks and Dungeoncraft are solid books for city and dungeon design (both full of some great ideas)
Book of Iron Might has changed combats in my campaign. Particularly I love the maneuver system presented here, the new uses for existing skills (all of them combat related) and the concept behind Battlemind and Arcane Battle feats.