This particular thread was intended to discuss the bidding rules that are included in the 41/42 ladder rules, which are currently as follows:
The current stable version, as of the above date, of TripleA is v18.104.22.168.
For 1941 with regular luck (Dice), the Allies bid is set to 8 IPCs.
For 1941 with LowLuck (LL), the Allies bid is set to 13 IPCs(*)
For 1942 with regular luck (Dice), the Allies bid is set to 9 IPCs.
For 1942 with LowLuck (LL), the Allies bid is set to 9 IPCs
(*) No bomber purchases are allowed for this game and bid combination
These IPCs may be spent on units to be placed on the board prior to game start. The IPC may be split by the allies in any way. The first restriction is that no more than one unit may be placed per territory. Naval units must go into a sea zone with existing Naval units of the same nation. Placement of naval units in empty sea zones or placement of, for example, British units with American units (and vice versa) is not allowed. Similiarly, ground/air units must be placed in the territories controlled by the same nation. However, ground units may be placed in territories that have no existing ground/air units.
Unspent IPC's from the bid can be divided up between the Allies for spending in future turns as the Allied player desires.
In the lobby, people generally follow these rules as a community even though lobby games are not generally ladder games.
The FAQ which is linked to at the top of the lobby message when you join, http://tinyurl.com/tripleaFAQ, also contains an explanation and guidelines for bidding on the third post down I think.