ah yes, not so good on big recordsets.
try this(changing PK and table name as appropriate)
SELECT * FROM tblitem WHERE ItemID >= (SELECT FLOOR( MAX(ItemID) * RAND()) FROM tblitem ) ORDER BY ItemID
or
SELECT t.ItemID FROM tblitem t JOIN (SELECT(FLOOR(max(ItemID) * rand())) as maxid FROM tblitem) as tt on t.ItemID >= tt.maxid