I want to send fax via internet , cost free. It is more than 1 file and I want to send them as it is 1 file.
I am going to use it in TURKEY and it can be a international sending fax.
I may pay for it and I want unlimited quota.

Try faxzero.com

Take note its limited to 3 faxes a day (2 pages each)

What is the most economical method of sending an occasional fax via the internet only?

I looked at services such as efax, etc but they involve a monthly fee. I may have a need to fax from home 1-2 times every few months but not enough to justify paying a monthly charge. I would be open to a pay-per-fax method and I would not need to receive any faxes.
Also, I do not have a phone line since I use wireless only. Therefore, I need this capability via the internet.

If you don't care about the cover sheet having an ad, you can use FaxZero.com.

Free Fax
*Free!
*Ad on the cover page
*Maximum 3 pages per fax
*Maximum 2 faxes per day

How can I send a fax via internet for free? How can I send a fax via internet for free?

I would just email, but my mom recommended this site:

http://faxzero.com/

How do you send fax via internet?

One method is to subscribe to a VoIP service that supports Fax as well as voice calls.
You can subscribe to a service that provides you with an ATA (analog telephone adapter) preconfigured with their service, or buy your own ATA and configure the ATA box for what ever service providers allow BYOD (bring your own ATA box) - many do allow this, but not all.
I have my own Linksys PAP2T 2-line VoIP adapter. It can function with Fax if you set the Fax line to only use G.711a/u codec. This is key for any VoIP service to work for you - it must support and use G.711a/u codec to accommodate Faxing (but not guaranteed to always work).
Some VoIP boxes support T.38 Fax codec, which is specifically designed to support Fax protocols over VoIP lines. Your service provider and ATA box both must support T.38 protocol to work.
InPhonex and CallCentric are two VoIP providers that support G.711a/u and Faxing. InPhonex can supply your ATA for you, and CallCentric is BYOD service only and supports both G.711 and T.38. Both services are pay-as-you-go and do not require contracts or commitments - a great way to test things out. (link is in my profile).

How do I go about sending a fax via the internet? How do I go about sending a fax via the internet?

Do you have a FAX modem? Piece of cake.

With my FAX modem, which appears in the list of printers, I compose a Word document (for example), then click Print. For the printer, I select FAX. This assumes you have a FAX modem and that you have configured it.

Via the internet - send in e-mail as text or as an attachment.