Calling all Maternity Fashionista's!

I recently moved to Northern California and I have a graduation ceremony coming up next month at my college in Southern California! I'm having a hard time finding a cute affordable dress that I can fit my bump into, I'll be 20wks by the time I graduate and I know I'll be even bigger! Any suggestions and where I can buy/order something that gives a good idea about measurements?  This will be the first time that all my friends and family will be seeing me with my baby bump so I really want to show it off 😊