Shin, a regular reader here, has a blog with a few tilesets you can use in Rpg Maker VX games. Mostly autotiles. He’s from Brasil so you’d need to turn your translators to “portuguese” if you want to read the text and comments from people.
Some are conversions of older japanese RM maker artist resources to VX format, others might be custom? (See post comments!) There’s a few there we haven’t seen before either way.
http://blogshinvx.wordpress.com/
By the way Shin, we found out about your blog when it’s visitors loaded the image from a post you made there about our RMVX autoshadow remove script. Thanks for passing it around! :)