The big bust problem has an easy solution... buy silk and cotton tank tops to wear under your suit jacket. You don't need to wear a conventional button-down blouse.
I would suggest buying good quality "classics" in a natural fabric. Don't buy "trendy." Yes, these classics may be a bit pricey, but they don't look cheap and never go out of style. Better to save your pennies and own just a few suits to begin with to mix and match. You'll have them for years and years. More economical in the long run!
A good lightweight wool gaberdine is virtually seasonless. Believe it or not, Lands End has some beautiful suits.
Also check out Talbots. They have incredible sales where you can get beautifully made high end clothing at a fraction of the price.
Some good, basic pieces to begin with:
Black dress pants
Black skirted suit
(black goes with virtually anything, so you can add a colored blazer to the black pants or skirt for a different look)
white shell
Then add:
your choice of pink, red, camel, and creme blazers.
Keep building up your wardrobe with classics. Add camel wool pants, a nice linen (or linen blend) jacket. (Remember that linen wrinkles like crazy!)
You can get an expensive look by wearing a classic suit and adding an inexpensive cotton tank top. Buy lots of these for a variety of looks.
Look here:
http://www.landsend.com/cd/index/fp/...93521826137000
and, I would recommend this as your first suit:
http://www.landsend.com/cd/fp/prod/0...93521826137000
And guess what? Talbots is having their amazing twice a year sale RIGHT NOW!
http://www1.talbots.com/talbotsonline/index.asp
This is a beautiful summer jacket in linen.
ttp://www1.talbots.com/talbotsonline/product/itempage.aspx?item=P54687&PFID=529&BID=S2006180234 83939C539CE81AA46E5A953A3&h=M
Don't forget to accessorize too. Invest in a good silk scarf, a nice gold necklace, and pearls.
Again, do this gradually. Take your time and look for quality.
One trick is to go into a very expensive store like Barneys of NY or Neiman Marcus to educate yourself on quality. Look at the fabrics. Feel them. Look at the tag and learn about different fabrics. Study how the seams are sewn. Take a look at the buttons. Then you can go to a less expensive store and look for the same details.
Happy shopping!