The great news is that all the Wonder Boy games is being released for the PS2 (goto Play-Asia.com) in Japan on the Sega Ages 2500 Vol. 29: Monster World Complete Collection compilation (this link goes to the Google translated page, here’s the link to the original Japanese page). From what I could read out of the translation, you get all the 6 Wonder Boy games (Japanese) + 10 other version (probably different console versions).
Here is the list of the 6 Wonder Boy games with Japanese names (Western names may be different):
- Wonder Boy
- Wonder Boy in Monster Land
- Wonder Boy III: Monster Lair
- Monster World II (aka Wonder Boy III: The Dragon’s Trap)
- Wonder Boy V: Monster World III (aka Wonder Boy in Monster World)
- Monster World IV
This a Japanese realese only, so you need a Japanese or modded PS2 to play it. The games is released on March 8 and can be ordered from Play-Asia.com.
The pictures are from Segadirect.jp.