It would be a lot easier to understand what car you need help selecting electronics for. Just to confirm when you say "racing", are you planning to race at a club with an organized group or just "bashing" around with friends in private?

Reason I ask is that generally, most bashers go with sensorless electronics to make things less complicated and less expensive. If you will be racing at a club, then typically there are restrictions to cell counts for each class and in most spec classes they will restrict motor size as well.

Generally 2S Lipo is used in most 1/10 cars with 540 sized motors (3650 cans).
Sensorless comes in KV ratings with 3000KV being a moderate choice
Sensored motors com in turn ratings from 4.5T to 25.5T with the smaller the turn the more powerful and 10.5T being similar in power to most 3000KV motors

Gearing is very important!

Some folks might opt to go with 3S instead of gearing up or selecting a faster motor, lots of different ways to tune for speed/temps.

4S-6S is generally used for 1/8 buggy with 4268 cans and larger 4274 cans are used in truggy. 2000KV is a moderate size motor for 4S.

Once you have selected a proper motor, then you simply choose an appropriate ESC for that motor, most brands will sell a combo with the ESC already matched to make this easy.

Low budget brand to consider is GoolRC
Middle of the road brand with high quality to consider is HobbyWing
High end brand with extra features to consider is Tekin

Trying to avoid writing a book, but this is the quick and dirty, happy to help you narrow your search once you give us some more specifics of car and plan for use.