Best of luck in the shopping and congrats on your upcoming shaadi. Wish you all the happiness in the world.
As soon as you get to paks, go to one of the booksellers and pick up the latest bridal magazines, they usually have a directory per city which lists all the shopping places you can go to.
The designers are based mainly in Gulberg, but are a right rip off! I guess you have to see and choose. I have mentioned a designer friend of mine in this forum, she is based in EME and does really nice stuff, i wouldnt recommend looking at her website as that does not do justice to her work.
With the current styles, I think longer lengths will border work, or even plain borders are in, but then again, fashion changes quickly, so when you get to paks roam around and you will see what is in!
Mens sherwani and clothes: Dulhas, Junaid Jamshed, again the bridal magazines should help. If you do a google map search on lahore and move your mouse around, you will see that it actually lists key shopping places etc. Otherwise use google generously!
For shoes and accesories go to Liberty Market in Gulberg and enjoy! There is so much choice!
Dinner set etc can be brought from Icchra.
Ask one of your inlaws to either recommend or take you to these places and ask for their opinion.