I was in the same boat when I first started - in fact, I delayed joining Numista for maybe 5 years even though it was my usual “go to” via Google whenever I needed to look something up.
Someone got a little too “enthusiastic" about some of the variations on some of the Queen Victoria pennies which I was looking up, so I thought “oh this is way too advanced for a causal beginner”.
Honestly, it's not as scary as it first appears & the site staff have done quite a lot to make it more user friendly over the last few years.
Once you've got the hang of how it works, it's actually a pretty solid website for keeping track of your coins & banknotes, and is very comprehensive.
For the most part, it's just understanding the filters. The “Issuer” is usually the nation (occasionally it's more an organisation), and change the all types to be “standard circulation” & “Circulating commemorative” for either coins or banknotes, depending on what you're looking for.
Unticking all the other boxes removes a lot of items, which makes it much easier to navigate.
The “Add filters” is basically an advanced search. The most useful ones are ruling authority (e.g. A monarch, like Charles III of the UK), year, and face value.
And if you're unsure, you just type in as much as you can & it'll pop out a shortlist of possibilities.
Give it a whirl with a few items where you know exactly what it is, and I'm sure you'll get the hang of it. But if it's still a bit scary, feel free to ask in the forums or drop me a message & I'll try and help. I pop by every few days. 🙂
You can also use this info page which tells you exactly what each filter does. https://en.numista.com/help/how-can-i-search-the-catalogue-99.html
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To answer your question though, I believe colnect & ucoin are the biggest other databases for coins. I don't like them (a bit too heavy on advertising I think, and I find their search features worse), so I can't recommend them but may be worth having a look, see if they work for you.
