Mothercare, all department stores, M&S etc have great breastfeeding rooms. Mothercare usually have highchairs, play pens and a few toys for older children.
At first I would use a muslin squares, tuck one corner under bra strap on the side i was feeding and use the other to sheild my dd's head. I breast fed for 8 months but after a while i just got really good at putting her on and no longer needed the muslin square.
In warmer weather i wore a vest and just slipped on arm out and popped my boob out while the other was covered, if i was feeling particuarly shy, i would out a cardigan on.
I actually preferred string bikini bra's to nursing bras, all you have to do then is slide the material to one side to get the boob out and and you can pull it back quickly if your baby suddenly pulls off. It's also really easy to pop your nursing pads back in.
Also when going out for dinner, I wore a black dress which crossed over my boobs, I found this great for breast feeding in restaurants as nobody realised i was nursing, it just looked like i was cuddling her. so you could buy some cross over tops/cardigans.
i never did really use big tshirts as i foundit more hassle trying to gather all the extra material up over dd's head andi aslo did not like showing my flabby belling to the world, i preferred the top entry.
but after a while my belly did go down, the muslin squares went and i just became so much more relaxed with it all so much that one time i spoke to my 18 year old brother for over 10 mins with both of my nursing flaps open. he was trying so hard to focus on my face. i was so embarassed!!!
i took my dd on her first holiday at 4 months and found feeding times a breeze, out pops the boobie and bobs your uncle - no bottles, sterilisation equiment, or sand!!! easy. im sure i would of had a stressful time if i had bottlefed her.
I loved breastfeeding and look forward to doing it again ... but not the first few weeks - ouch!