I see that you ordered the VOLT, that kit should treat you right until you are ready to move to something else. And depending on your experience with it and your behavior in taking up a new hobby, let's face it - we're here because most of us treat eCigs as a hobby and a way to stop using the stinkies, the VOLTs will last you a long time.
Now if you are still 'WANTING' after using the VOLT For awhile I would suggest getting into a Bigger Battery. Most people will say Joyetech eGo of some size battery, 650/900/1000/1100/-18650-MOD/TWIST what have you, and for the most part they would be right.
The eGo provides two Connector Options. The Connection Options are the 510 in the Center of the Battery where the Positive Post is located, and then the eGo threaded skirt on the outside of the center's 510 connection. This gives you two options in choosing what you can buy. An uneducated guesstimization on the percentages of all the Batteries on the market that use either the 510 or the eGo connectors would probably be over 80% of total share. So you cannot go wrong with a Joyetech eGo. As usual there are about 14 million companies that make Knock-Offs of eGo batteries since all this stuff is made in China.
When you are ready to move to an eGo, for instance - you don't have to buy an eGo, do not buy a Joyetech eGo-Ts/Cs starter kits. The eGo-Ts are notorious for Leaking after a good week of use. That is what happened to me and no matter if I put a Brand New TANK and Rubber Plastic cover on the bottom of the TANK; after I took the first or second drag off of the eGo it would ALWAYS Flood the Coil which was very frustrating. Also the cost of the Coils for the C are usually around $20 for a Five Pack. Which for this eCig industry and literally everything being made in China $20 for 5 coils IS OVER-PRICED.
But, you can piece together your kit. There are vendors out there that have their own styled kits of eGos where you will get a few Vision Stardust CE4+s with replaceable heads for instance and may be a bottle of two of juice and charger for USB and Wall converter. Nobody ever really sticks to Joyetech offerings beyond just having the Batteries.
Right now you can get some eGo Twist Knock-Offs for less than $20 a piece, well $19.99. For instance:
eGo C Twist Variable Voltage Stainless
Two of those should get you going on the eGo side of things very nicely - and being able to adjust the voltage to suit whatever juice you are vaping is a HUGE Plus.
Then of course you will need a charger for these:
eGo Chargers
Oddly they don't have a USB to WALL converter in the lot. Shouldn't be any more than four or five dollars US! But since you are in Europe you won't be using an American Wall Outlet.
Lastly If you could afford it too, and if this were me, I would get the Two Twist and then one of those Lava-Tube/Lambo Knock-Offs already listed. Their Variable Voltage has a greater range and the device is adjustable in .1 Volt increments. The Twist is only Adjustable in .2 Volt Increments and doesn't go any higher than 4.8 Volts which is more than enough for most of us using the right ohms on our Attys, Clearos, Cartos, Tanks and whatever.
If you do get a Lave-Tube/Lambo don't make things more complicated before you know what you are doing or are comfortable doing it. So anything with an actual 'REAL' Rebuildable Atomizer should be avoided. Speaking of the devices where you actually buy wire an wick to wind your own Atomizers. Don't let that get you confused withe the Vendors who advertise the Stardust CE4s and Kanger T2s as being Rebuildable. They actually have replaceable HEADS and Changeable Coils. Sometimes in the title of the Products they will be listed as say "KANGER T2 CC". Which means you get to keep everything and you only need to change out the Head or Coil, which are the same unit.