In general you will find Henkels, Wustoff and Sabatier's top of line the best values when found at a close out (around $125-150 usually with other add ons).
I believe 5 star/ProS is Henkels and Classic/Grand Prix is Wustoff's top...Grand Chef/Province is Sabatiers.
If you have no knives, buying an 8 to 10 piece set often turns out to being what it would take to buy 2-3 knives a la carte.
Then you can add speciality knives as you need to.
Kershaw/Kai Shun are nice albeit expensive ($120 is typical for the Santoku) knives.
For $50 if you can find a Tosagata Hocho that would be your best bet for a Santoku. Or try to do $125-150 and get a nice starter set.
Å