RollerbladeFLA

Hey guys, im about 19, 6' 1", and 160 pounds or so. Very fast metabolism, and I exercise by skating, (aggressive skating)
I smoke fairly often, usually almost daily. and I have applied for a job which I wouldnt start til 5-20-07. Yet they set up an interview for me this tuesday, 4-17-07. It is for a Sales job at Kanes Furniture.
The website has information about drug testing but it doesnt state when the test will take place (obviously).
I smoked a joint last night, so I think it would be pretty safe to say if I take a test this tuesday I will fail, so im more so asking if it is common that they would test right after the interview, and if so is there any legit way out of that.
Im moving and really need to secure a good job.
So I guess to sum up my questions because I tend to write a bit sloppy.

1) Do most places test on the same day as the interview? (or if anyone has worked at Kanes furniture and has specifics that would be amazing.)

2) If I find out they do test, what are my options considering I will have smoked last night and the test is tuesday.

3) Has anyone called the employer anonymously and asked when they do drug tests? (this may sound stupid but who knows, it might work)

Thank you everyone!