Possible things to study:

• [2011-06] Books that I bought:
  • Domain-Specific Languages — Kinda basic and overly thorough... but it's nice to have a gentler introduction. It's also less radical, and generally covers just the more-accepted areas.
  • DSLs in Action — much faster-paced, covers newer things
  
  
• [2011-06] Metaprogramming facilities in non-homoiconic languages.
  Some languages are lauded as being better at metaprogramming than your typical lanugage:
  • Ruby [1]
  • Groovy [1] [2]