I guess the first question would be whether you have the exact same index information as you had in MSSQL.
What is the output of
EXPLAIN
Select left(Amazon_Items.Product_Description, 1) As IndexLetter, Count(Amazon_Items.Amazon_Product_ID) As NumProducts
From Amazon_Items
Inner Join site_amazon_items On Amazon_Items.Amazon_Product_ID = site_amazon_items.Amazon_Product_ID
Where site_amazon_items.Site_ID = 5
Group By left(Amazon_Items.Product_Description, 1)
??
Mike Hillyer, Technical Writer
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