Where: For me fuel costs mean I would only go as far as Dunfermline for a one day and my preference would be as local to me as possible eg at Egglady's place I'd do 2 days! The 2 day course at Falkland, or the 3 day woodfest event even, tho more expensive than I would probably want, means I'd need a real bargain to go further afield if I do find money to go.. I'd enjoy it but it isn't a priority so has to be easy and/or cheap to make it one!
What: I understand round baskets are easier than oval ones but whatever is easiest for a complete beginner but produces something I can actually use rather than purely decorative (or not!) - log basket, egg basket, wool basket, laundry basket - any size would be useful if I could replicate it at need but I don't need more ornaments..

When: if it's a full day then I want to set off and get home in daylight so I can see animals not work entirely in the dark for 2 days while rushing about the country in between

So for me no later than autumn. Dead of winter is hard enough without a day or two driving somewhere and being away all day, particularly if things go wrong at home or the weather is bad..