Well back to topic, The first thing, you should do all the maintenance required, change fluids, have it scanned in Pepboys (its free) or any major automotive store, write down the codes and bring them here so you know what is needed to be done.
After that If I were you I would save up money to buy some lowering springs and shocks, the lowering springs depends on how much you want to lower the car there are many springs like Eibach, Megan, Tein, Progress and they all have different drops. The Teins are the most used in this community and in a above post there are photos of a car using them, just need to search your application 99-03 V6 Galant or 00-05 V6 Eclipse as they share the same suspensions and engines. All the springs packages come with all 4 necessary springs. In the Tutorial section theres a How To so I encourage you to take a look there. When Installing Lowering Springs you should buy new shocks the most used are KYB GR2s or KYB AGX (they have adjustable stiffness and are more expensive).
After that I would go for the rims it doesn't matter if you dont have the money right away just save up for them, its worth it, the rims are whats going to make you really fall in love with your car, you can buy some OEM Evo rims or you can look around in the forum, you can look at this thread
https://www.thegalantcenter.org/show...favorite+wheel take ideas. The rims buy most be 5 x 114.3.
I know it a long read but it should be helpful, for me when talking about looks these two things are the most important.