Revisit the familiar territory that was first introduced in S2: White Plume Mountain by Lawrence Schick and later revisited by Bruce R. Cordell in Return to White Plume Mountain with this classic 2nd Edition Adventurer's Guild tournament called Dragotha's Lair. Dragotha's Lair is for five to six characters of 6th to 8th level and requires the use of the 2nd Edition Player's Handbook (AD&D 2e) and the Dungeon Master Guide. Not only does this adventure feature a dracolich and its lair, but it also comes with pregenerated characters and two maps. You don't need to have Return to White Plume Mountain to run Dragotha's Lair, though it certainly ties in well with that epic adventure.
This is one of the most commonly-encountered RPGA scenarios - it was made available both in print and as a PDF.