Please don't be discouraged. I'm on a very tight budget too, I got an amazing cold frame from Amazon for about £30 last year, and I find Aldi to be fab at gardening things. They've got PVC 3 and 4 tier greenhouses in at the minute, and they had fruit trees a couple of weeks ago. I don't know if your local Aldi will have any, but they had raised bed kits for a tenner. They are very good if you can get there on a Sunday and Thursday when the 'special buys' come in.
Poundstretcher and Wilkos are also very good, but can be hit-and-miss as to what they have in. I also save my Tesco clubcard points and use these on gardening offers. They have an offer ATM for strawberry plants, something like £4 worth of points for 10 strawberry runners (delivered). They also have fruit trees on offer, but they're about £12 worth of points (I never seem to accumulate that many).
I hope it's just a huge misunderstanding, hopefully the chap took all the stuff away thinking it was his Mum's, with any luck it will be sitting in his shed, and the police can get it back.
I keep trying freecycle to see if I can find a shed/greenhouse/chicken coop, no luck as yet! I get emails every day, but it's mostly folks thinking Freecycle is like their own personal Argos - they even specify the colour of the leather sofas they want!!!
Chin up, hopefullly you'll make lots of friends with other allotment holders when they find out what's happened, and they can help you replace some of what you've lost.
