Morph maternity pants are comfortable and well-tailored. I used to go to office smartly dressed in Morph pants and shirts and the compliments just keep flowing in. Even their nursing bras are wonderful!They made feeding easier and comfy.
Loose clothing isn't necessary.. people are just crazy about other people's pregnancies, for some reason. My fiance's grandma told me wearing tight pants would block the blood flow to my child (which makes no sense considering my heart and baby are ABOVE my pants).. but no, it's not true. As long as you're comfortable, that's all that matters.
And I found some pretty cute maternity tops at Target (online has a much better selection than in stores) and Old Navy (same with them.. I'd look online first). They have cute dressy tops and some plain t-shirts too.
As far as pants go.. get a belly band! You can wear your regular jeans, just unbuttoned/unzipped and put the belly band over it.. it covers the part that's unbuttoned/unzipped and just looks like you have a long tank on under your top AND it supports your belly. Good luck!