I've just realised - my new campaign starts tonight, and one of the players has cancelled. That's generally not an issue, except that since his was the only character with a Charisma in double figures, I had planned to use him as the vector for my first adventure hook! Oh dear.
As a rule, I start a new campaign in the tavern, as this tends to be the focal point of the community. I would go with the temple, but players tend to be a bit wary of having their characters be too religious.
However, I try very hard to avoid having that first hook come to them in the tavern, because that tends to be old hat. Instead, I use that initial scene simply to build mood, introduce the PCs and a number of NPCs who may or may not be important later, and so forth. Basically, the idea is to provide the players with a sense of "this is what we're fighting for".
I try to have the first adventure hook come to the PCs through their backgrounds, which tends to be a bit tricky as these tend not to be very fleshed out at this stage. However, as no man is an island, there's always someone who can call on the PCs, whether because they're in trouble, or (better) because they have a job offer or an unexpected opportunity for them to follow up on.
Failing that, just have them see some "help wanted" posters. I'm of the opinion that the players really have to work with the DM at the start of the campaign - it's not the DM's responsibility (well, not solely) to think of a reason for the PCs to go on the adventure. If they don't the campaign will kinda suck. So, it's for the players to come up with reasons why their PCs would go on the adventure.
Incidentally, my new campaign is set in the kingdom in which the monarch and many of the nobles are off on crusade. The initial hook features one Aldus, an acolyte of the temple of Heironymus (sp?), who was an acolyte at about the same time as my absent PC (albeit in another temple), and with whom the PC has a friendly rivalry.
Anyway, it seems young Aldus has gotten himself in a spot of bother, and his superior the Prelate (one of the most influential priests in the city, and thus one of the most important men left in the kingdom) is looking for a few "capable and discreet" people to help sort it out.
Things are going to get a tad more confusing once the Prelate sends them to the Velvet Glove, the most notorious crime boss in the city...