Blitz3D Engine

Blitz3D provides a simple yet powerful environment for game creation - simple, because its based around the popular and easy to use BASIC programming language; and powerful, thanks to a highly optimized underlying 2D/3D engine. ($100)

http://www.blitzbasic.com/Products/blitz3d.php

Dark Basic

DarkBASIC allows you to create your own games, demos, slideshows, even business applications using the easy to understand BASIC programming language. Even if you've never coded before, just follow the in-depth tutorials and you'll be generating results in minutes! Harness the power of Direct X and make 3D objects come to life in just a few simple commands. ($39.99)

http://darkbasic.thegamecreators.com/

DxStudio


DX Studio is a complete integrated development environment for creating interactive 3D graphics. The system comprises of both a real-time 3D engine and a suite of editing tools, and is the first product to offer a complete range of tools in a single IDE. (free)

http://dxstudio.com/features.aspx

3DGameStudio

Gamestudio
is the first all-in-the-box game development system, used by over 100,000 artists, hobbyists, programmers or game development companies across the world. Our clients range from kids who use Gamestudio for their first steps into computer programming, to multinational corporations who use the software for creating all sorts of simulations and advertising games. (various prices)

http://3dgamestudio.com/

Nighthawk Arts RPG Templates

The Nighthawk Arts RPG Templates, are a scriptpack/template for 3D Gamestudio.That it is a template, means that you can choose it in the templates list in WED (File | Map Properties | New Script).
The NHA RPG Templates are completely free!

http://rpg.nighthawk.dk/center/

Quest3D

Quest3D takes care of the entire process from importing your models to delivering the final product. The template system of Quest3D lets you create your own templates for things you use very often. For example you can create a template of an environment, menu structures and user interaction so you can turn a CAD model into a presentation within minutes.( EUR 999)

http://quest3d.com/index.php?id=6