#Perl 5, 243 bytes
$}=" bottle";$s='s';$o=" of beer";$w=" on the wall";$i=99;while($i>1){say"$i$}$s$o$w, $i$}$s$o.";$s=''if--$i<2;say"Take one down and pass it around, $i$}$s$o$w.\n"}say"$i$}$s$o$w, $i$}$s$o.";say"Go to the store and buy some more, 99$}s$s$o$w."
(using the free -M5.010 switch for "say" instead of "print")
Cheers.