Zuki,
Wow ...Saint Valentine’s Day, huh? We don't have much time then!
OK - first thing to do:

1) Make a set list of ALL your best live numbers. List them by category.
i.e.:
dance, latin, slow, swing, etc
2) Next make a list of the TYPES of styles/tempos you are MISSING from your live repertoire.
i.e.:
hip-hop, line dances, cha-cha, etc.
3) Ask around, or Google to find the most popular of these tunes available for free downloads.
i.e.:
Cha-Cha - "Never on a Sunday"
Hip-Hop - "Bust a Move"
Line Dance - "New York, New York"
Two Step - "All My Ex's"
*** These are just a sample of how to look for million sellers to "pad" your dance repertoire.

After you have the songs on the Laptop - put them in folders so you can find them easy, keep the folders open and be ready at the drop of a hat to access them.

I have audio inputs on my Yamaha psr3k, so I run the Laptop's headphone outputs into an external headphone amp (Rolls), just to boost the signal, and then the mix comes through the KB along with my voice. That signal is fed to the PA or house system.

The tricky part is deciding WHEN you use a file or play live.
Here are a few points to consider:

1) It's hard to follow a 16 piece big band arrangement with an omm-pah pattern, so I try to use MP3 tracks at the end of a set or right before a ballad that I KNOW will pack the dance floor ( aka: "Crazy" )
Keep your eyes on the dance floor ( or the EYES of your listeners) and pick the NEXT rhythm while you're playing the current song.
i.e.:
You're playing "Runaround Sue" - they love it, and they're dancing to it ...... do you play another jitterbug, or is it time to slow it down, or change it up somehow? Decide that B4 you end the Dion tune, so you are ready with the next dance beat.
I think it's more important to pick a beat than a song. I try not to play 3 of any one type in a row, no matter HOW many people like it. What about the ones that don’t like it? dON;T MAKE THEM WAIT TOO LONG FOR A DIFFERENT CHOICE.

( Dam caps lok !!! grrrr )

If I pack the floor with a ballad, then I give them a second one before I change the rhythm to say ….. a cha-cha like “Under The Boardwalk” or “My Girl” – that keeps the tempo change minimal ……. After the latin deal, then you can pump it up with a Rock/Disco/R&B type song.

Anyway you choose to run your sets – just be aware of HOW you need to place the MP3s within the set. If you start playing 3,4,5 DJ tracks in a row ……. You’ll never be able to compete with the energy when you go live.

As for download sites – iTunes, Van Basco, Limewire …. Anyplace that you trust. MOST of my files are from my personal CD collection, but I do use downloads too.

Be careful, be smart and be forgiving to the dancers if they prefer dancing to the original over an arranger’s pattern. They don’t ALL work for all songs. It’s YOUR job to pick the right style, right pattern, right tempo, and right order for ALL the songs of the night.
Control the pulse of the room, and you control the crowd. Once you let them tell you what to play next, or how to do anything – you’re lost.

Take requests with a smile, and play them when you think the ENTIRE room will benefit from that selection.

Just one man’s way of working the room!
Good luck – although on Feb 14th, most people will have more on their minds then dancing! You’ve already got an edge!