I had a look at the blue yeti + snowball and I wondered if it was actually worth it buying one.
The one I use ATM is the mic on my laptop. Realtek high-definition auto is my current one. Is it worth it? Also, if it is worth it, any recommendations?
That depends on how series you are, what your viewerbase is, and how many views you get.
Integrated mics are generally poor, headsets are good for starting out-mid range youtubers, and external mics are for people who take it very seriously.
If you eventually go external, an XLR mic is the best way to go, such as the AT2020, or AT2035.