I like to buy the frozen fish filets. They are less strain on the wallet than fresh and if you prepare them right, then you won't notice the difference.
I use those Steamer Bags (i believe they are Ziploc's) and steam my fish. I add Mrs. Dash seasoning to the fish before I cook it in the microwave. If you take one of your frozen filets, put it in a steamer bag, sprinkle seasonings on top(MLS, pepper, Mrs. Dash of your choice) then pop it in the microwave for 3-5 minutes(depending on your micro) and voila, a fresh piece of steamed fish that has great flavor.
Now, it's not the best you will ever have, but for $5 for 3 pieces of tuna, I can sacrifice a little quality.
I also like to use the steamer bags of frozen vegetables. You can often find them for less than a dollar a bag and they are so simple to make.
After I follow the bag's directions, I put them in a container with MLS, pepper, Mrs. Dash, and some of my diet butter and that makes me like 4 servings that stay pretty crispy over the next several days. I like the Italian seasoning for green beans and the chipotle seasoning for broccoli(trust me, it's great)
I know these aren't anything too fancy and S4L will probably tell you that they would prefer fresh over frozen, but I continue to lose weight and it works for me. I hope this works for you too.
Continued success with S4L. Despite my goal on here, I will change that when I hit it. So I still have a ways to go.