I went through valves, transistors, IC's - more or less ending up constructing early computers from components I had to import - it was too early for them to be available in the UK. In the day, I designed and built because there was much less available back then ready built, than there is now. Ready built is much cheaper than sourcing and building yourself, if what you want is available ready built.
Simple kits are a really good starting point, with all the components you need in the box, even better if the kit serves a some useful purpose. Components are not so readily available as they used to be, when most towns had electronics shops around, so ordering by post is the only way. Gone are all the war surplus electronics dealers apart from one or two. Ebay is a good source of components, either from the UK, or after a months delay even cheaper from China.
A soldering station is almost an essential investment, but a basic soldering iron would do as a starter, plus a multi-meter. The range and cost of other test gear is vast, best acquired only as needed, if it is needed and at a good price. I have acquired over the years a massive range, worth many thousands of pounds.
Joining an Amateur Radio club is a good idea, they may well have access to lots of experience and test equipment, plus maybe a licence at the end of it.
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