Welcome krazykate.
Your landlord can't just chuck you out. He needed to have gone through the proper channels by taking you to court to have you removed legally.
The problem is though, if it was you and your mate both working from the flat, you are commiting an offence as it then becomes a brothel, which is illegal. You need to be aware of that for the next place you do move into, if you're not already. And again, if you do move and the both of you are working out of the same flat, you'll encounter the same problem of neighbours complaining that there's too much traffic. Maybe you could consider doing seperate days to each other so you don't get too much traffic on some days.
Sorry I can't offer you any advice on where to move to next. All I can suggest is somewhere that doesn't have a doorman/concierge, a security entrance (i.e. to be buzzed in) would be good and somewhere busy enough that regular traffic will go unnoticed.