@polv already gave pretty good advice, and I definitely encourage everyone who comes across this post to at least install Yomitan (hello, lurkers 
) There is one thing I could add, though:
For sentence mining, I was pretty happy with iKnow, but I don’t know if the free coupons are still valid… if they are, here is a link to them, but you should keep in mind that it is far from being immersion.