How are you doing it? DD used to sit and eat breakfast with DH. No bowl for her, she just used to grab a bit of banana or berry. Don't bother with baby rice vile muck. If she is getting upset, change your approach. She doesn't need to get a lot down, just get used to it.
I agree with Sir, it just sounds like she isn't ready yet - there's no magic switch at 6 months. Just wait a week or so then try again rather than trying to force the issue now. Or just let her sit with you while you eat, give her a couple of bits of food to play with and don't worry about whether or not she eats it.
Some of the foods we gave early on include steamed and roasted veg, pieces of fruit, toast fingers, sticks of cheese, pasta (fusilli or other large easy to hold shapes work well), rice cakes, strips or chunks of meat. Keep the pieces fairly large at this stage so she can pick them up.
The blw book is Gill Rapley's book - there's one about the principles behind it and also a cookbook which covers the basic principle as well. But tbh, they aren't necessary as there's plenty online about it and as long as you avoid foods they can't have, like honey, you can't really go wrong.