Have a whizz back through the thread, because I asked the same question last year. But, basically, there are two flavours of playing Pokemon. Theme decks, where you get 60 cards and basically don't alter them at all, and just boosters to then construct a deck from scratch. My gf's daughter has been playing for almost a year now and when she's not being a tired grump she's basically nailed the theme deck side of it. She's got quite a lot of them now, too. As a rule they're seemingly getting more powerful with each release, so very recent ones against older ones is a not-bad quite-invisible handicap if you want to play against them without having to fiddle it.
Compared to a well-made deck, every theme deck is crap. So obviously that is a very different kettle of fish, but I've not tried moving onto that stage with her yet, because I'm not sure she's really got the luck/controlling luck aspect of the game yet. Variance isn't exactly an easy concept for grown-ups, otherwise deck-building games wouldn't be much fun. But theme decks are fun, and she gets a few boosters every now and again. So we're building towards that stage.
I never looked for Pokemon TCG stuff while I was in London, but I think Leisure Games is probably a decent shot, although they don't seem to have any events. The big Forbidden Planet on Shaftsbury Avenue must sell them too. You can look for authorised events on the Pokemon website:
Non-obvious stuff I've picked up:
- Get something that they can lean their cards against. If you're getting a pile of cards in your hand and you have very small hands, it's easy to drop them.
- You can get great deals from people who sort of started getting into it and then stopped on eBay. BUT the number of fake cards is ridiculous. A very notable percentage, including common ones. If it was just the rarest and most powerful ones it wouldn't be too bad, but it's literally everything.
- The app version on tablets/PC is great. You can scan in the code cards you get with boosters, but you can also buy codes on ebay to feed in. Older sets are less valuable so you can get a ton of cards that way, or newer sets are basically the currency for trading for specific cards. Amazingly/wonderfully there is no in-app purchasing apart from the currency you build up by playing the game. So it's completely safe on that front. It encourages you to join a forum and there is a chat bit in there, but both are very easy to avoid.
- They literally never realise that you're making them read really complicated words and do maths. It's genius.
- Also genuinely good fun.