How to get a homemade bakery style cake?

Sorry but store bought is usually high in chemical stableizers, artificial additives, and other chemicals to make it the consistency you love.

The best you will be able to achieve is something close.

If you want actual help, it would help us help you if you provided as many specifics as possible about what you're doing, what's going wrong, and what's going right.  

It's pointless to address the infinite possible errors without more information.  For instance:  How long do you preheat your oven?  How accurate is it?  Do you use the right size pans?  Where do you get your recipes? Do you over-mix?  Add your eggs one at a time?  How fresh is your baking powder?  Do you measure before or after sifting?  Do you use AP or cake flour?  Etc., etc. 

If you're an occasional baker, I suggest limiting yourself to a few cakes -- like genoise and pound cake -- and mastering them before moving on.  

Consider the above as generic advice.  But here's something specific:  There are much better cake bakers here than me. 

Good luck,

BDL

Both of the above replies are spot on.

90% of the commerical bakeries use mixes: Some contain emulisifiers, most contain a varieity of strarches, leaveners, egg replacements, dehydrated pulverized fats,  as well as colours (yellow) and flavours, stuff like sodium benzoate creeps in too, which gives it a heckuva shelf life.  Yech!

What is the consistancy you want?

As BDL suggests, try genoise (plain sponge) or pound cake first.  You can fool around and subsitute some of the flour with corntarch or roasted flour for a "lighter" feel, add more yolk for a richer feel (and natural yellow colour), add finely ground nuts, etc.

Personally, I take pride in  that my cakes don't taste like a "regular" bakery products