Could someone kindly provide information on the different alphard models or trim levels? Perhaps there's a page/site somewhere that you could refer me to? 

Thanks in advance

Personally I found this blog very handy http://eightseaters.blogspot.com/2009/08/what-are-those-model-code-mean.html

 

if you search for old entries from August 2009 there is a lot of more info about each trim. Very handy blog in general.

 

And here you have more detailed information for each year/model/trim

 

G series: http://auto-japanese.com/catalog/index.php?action=3&company=TOYOTA&model=ALPHARD+G

 

V series: http://auto-japanese.com/catalog/index.php?action=3&company=TOYOTA&model=ALPHARD+V