I currently have wire anttna up using a
WiNRADiO Long Wire Adapter and am unsure if i should add a preselector and/or tuner to my setup? Oh and the reciever I'm using is a satellit 750.
Honestly, with that kind of receiver, it's not worth the extra cost.
Eventually, if you decided to invest in a higher-grade receiver then it might make more sense. A lot of newer receivers (and SDRs) do not need this extra option. A medium to high-end SDR usually provides this extra hardware built-in. Most true "HF Receivers" already have a "high-pass filter" built in. This is not a pre-selector but it's good enough since the receiver circuitry is usually good enough to not need it.
The Longwire adapter you have is an un-un -- which is similar to a balun -- but it's unbalanced to unbalanced. In this case, the wire end is just a random wire. The un-un probably uses a 9:1 ratio but it may be something custom.
This combination is fine for what you have now.
You didn't say if you live in the city or in a rural location. The biggest question is noise. How much RFI do you put up with, etc. If you're overall noise is low then you probably won't need to change anything.
If you are in the city and are hearing a bunch of buzzing or repeating signals (that seem to show up every few khz) then you likely need to solve your noise problems.
Depending on your noise level, your antenna is probably OK. If you are in a quiet location, then you may want to invest in an alternate antenna. A amplified loop is a good choice. They are not cheap so there's an initial investment involved but it can really change your listening experience.
Again, it just depends on how serious you are about the hobby and how much money you're willing to spend.
Since you asked, here's a cheap option if you're willing to spend the extra cash. The only downside is that you'll need a couple of custom coax cables or use adapters to convert the BNC to PL259.
This is a pretty simple device to use and fairly straight-forward.
http://universal-radio.com/catalog/preamps/2964.html