Deciding on a phono preamp


I have a Thorens TD160b MKII turntable with an Infinity Black Widow tonearm and a Grado Green cartridge. I think that I have had the turntable and tonearm since the early 80"s and the cardtidge since the late 90"s. I can't remember ever using this turntable let alone with any kind of a decent system so I have no idea what it actually sounds like or is capable of.

I now have a fairly decent solid state system that I am considering connecting it into however it lacks a phono input... don't they all now.

Preamp - Anthem AVM-2
Amp ATI 2000 series (200wpc)
Speakers Energy 2.3i
Sub 15" 500 watt sub (kind of home made).
Blue truth interconnects
Flexegy-6 River wire to the speakers

I am trying to get a feel for how much I should invest in the phono preamp.

I was contemplating just getting a preamp in the $100-$200 range but if the TT and arm are worth it I was thinking of moving up to something like the Pro-ject tube preamp and then getting another cartridge.

Any thoughs??
pechichi
I believe the model is the Adcom GFP-565 preamp this is a serious and well built preamp with a very good phono section.
Thanks for your responses.

Schipo - thanks for your response but I don't think that I want to get into another complete solid state preamp, the Anthem is sufficient at this time, if I did want to go this route I would likely go with a tube one.

Wwshull & Grinnell - I did look over the zphono and I am not completely sold on that one yet.

I am really leaning on going for the Pro-Ject Tube Box SE2 which is in $600 range new. What is good about this one is that for a tube preamp it can support both MM and MC cartridges. Although it doesn't look like the black widow is compatible with a MC cardtidge it would leave me room to move into one by getting another tonearm down the road
I would stronlgy suggest the Dynavector P75, either the older mark 1 or the newer one. I had the older version and it is a bargain as far as sound and adjustability. I think they sell for about $400.00 for the older one. They are very well built and don't take up much space. You will have to spend 3 or 4 times the price to better it by any margin.

Although it doesn't look like the black widow is compatible with a MC cardtidge it would leave me room to move into one by getting another tonearm down the road.
If you like the overall compliance/effective mass match of the Grado Green and the Black Widow, maybe you should try a Prestige Gold. Or if you want to thoroughly modernize while getting a good compliance match, how about the new Ortofon 2M Bronze or Black?
Ibog- I had looked at the DV too and that is a really good contender, but there is just something about the tube thing that I can't seem to get over right now. Curoisity will most likey kill this cat.

I actually picked up the Grado Green just to have something to use the TT to see if it works since I had never used it since it got it. If I go ahead with this project I will definately get a better cartridge. I was looking at the Grado gold and the Orthofon OM30 or 40 instead of the 2M. They have a higher compliance than the Grados (25 vs 20 on the Grado's) I'll take a look at the 2M, thanks for the suggestion.